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"Evaluating Superpixels in Video: Metrics Beyond Figure-Ground Segmentation", by Peer Neubert and Peter Protzel
Day 3, Session 06. Wednesday 11th September
This times the noted dissertation segments sequences. Get ready for the wise words and a nice cake! The event is open everyone. :)
(The reflection of the the photo capturer can be seen in this picture.)
20. November 2019, Jugendstilhörsaal der MedUni Wien
“Multiparametic Diagnostics and Theranostics of Tumors”
Fabian Kiessling, Universitätsklinikum Aachen
Abstract:
Significant advances have been achieved in elucidating molecular regulations of cancer and numerous disease-related markers were identified. Additionally, imaging technologies steadily improved and are providing detailed insight into tissues’ morphology, function and molecular regulation. However, there is still a need to identify and quantify the most relevant information and to bring it into a mechanistic context.
In the first part of my talk, I present advanced imaging strategies to characterize tumors by assessing various “hallmarks of cancer” using non-invasive imaging and to assess therapy responses. In this context, I will discuss novel computer applications to improve data processing, lesion detection and segmentation as well as radiomic image analysis. However, taking a study on hepatocellular carcinoma therapy with a multispecific tyrosine kinase inhibitor as an example, I will also show that correlative analyses do not always lead to correct conclusions on biological mechanisms and that the interconnection and impact of the observed changes need to be understood.
The second part of my talk will be dedicated to drug delivery. Here, I will show how imaging can be used to improve the preselection of patients to therapies and discuss the value of nanomedicines and active targeting. Furthermore, I will highlight the potential of ultrasound mediated theranostics to overcome biological barriers and to improve tumor perfusion.
(c) MedUni Wien / Kovic
The segmentation between the archway stones is not showing. I will either have to increase the space between them or increase the render quality.
This monument, like the court tomb in Laraghirril, which lies 1.5km to the W, stands in the relatively low-lying plain of good agricultural land stretching from Trawbreaga Bay on the W side of the Inishowen peninsula to Tremone Bay on its NE flank.
The monument, orientated approximately E-W, has been considerably damaged. It consists of the ruins of an unroofed segmented gallery, now almost 10m in overall length, set in a long mound. According to R.S. Young (1897), the gallery had been covered by a cairn of earth and rubble until it was exposed by the tenant when searching for stones. There are a considerable number of sizeable slabs and variously sized fragments of others lying at the site, particularly at the eastern end of the gallery. These are not shown on the plan. According to local information, dynamite was used to dislodge stones from the structure in the early part of the 20th century. Boreholes visible in three of the larger blocks of stone seem to confirm this.
The mound measures c. 30m E-W and narrows from c. 13m at the W to 10m close to its E end. It reaches a maximum height of c. 1m. Apart from spreads of stone near the gallery, it is largely grass grown. In 1982, when the plan published here was made, an extensive dump of material derived from field clearance obscured the western end of the mound. Since then similar material has been dumped in smaller amounts at other points adjacent to or on the perimeter of the mound.
The gallery appears to have consisted of at least three chambers. That at the E is largely destroyed, and all that survives are three orthostats of its northern side. The easternmost of these is 0.6m in exposed height. The second rises 0.4m above the top of the first. The third lies 0.6m W of and is 0.25m taller than the second. It partly overlaps the segmentation between the eastern and middle chambers. This segmentation is marked by a jamb placed longitudinally inside the line of the N side of the gallery, with an inclined sillstone set at right angles to its E end. The jamb is 0.8m high and rises 0.45m above the sill. There is sufficient space between the end of the sillstone and the S side of the gallery to accommodate a second jamb.
The middle chamber is c. 3.5m long and 1.7m wide. Three orthostats form each side. On the N side the easternmost orthostat and the stone next to it are the same height as the segmenting jamb already described, but both may originally have been taller, as they appear to be broken. The third orthostat on this side is a tall pillar-like stone that rises 0.6m above the other two. The heights of the orthostats on the S side of this chamber from E to W are 0.95m, 0.7m and 1.2m. A displaced slab (not on plan) lies to the S of this chamber.
The jambs dividing the middle chamber from the western chamber are set longitudinally inside the gallery walls. These are 0.8m apart but are only partly opposite each other. The southern one is 1.6m high. The northern one leans southward across the gallery and if upright would be the same height as the southern. The sole surviving sidestone of the western chamber adjoins the leaning jamb. It is 0.9m high. A large displaced slab, measuring at least 1.7m by 1.6m and 0.4m thick, lies across this ruined chamber. Its southern end rests on a stone protruding at an angle from the cairn material exposed here. Approximately 1.5m WSW of this is a firmly set stone 0.6m high. The status of these two stones is not clear. According to 'Maghtochair' (1867, 15), a large roofstone then covered one of the three chambers, but he did not specify which one. The large roofstone is also mentioned in an OS Name Book of 1848.
Whether there were more than the three chambers now apparent in the gallery cannot be established, nor is it known at which end the entrance lay.
The above description was published in the 'Survey of the Megalithic Tombs of Ireland. Volume VI, County Donegal.' Compiled by: Eamon Cody.
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Photo by Vicki Rogers
Some sandstone in the Santa Cruz Mountains have variable levels of calcium carbonate segmentation resulting is certain parts being softer than others. The heavy rainfalls in our mountains contain carbon dioxide from the air which seeps into the sandstone and dissolves the softer areas of calcium carbonate holding the sand grains in place. During our dry season (we do have a short one,) the calcium carbonate is drawn to the rock's surface forming a deposit that resists erosion. This leaves the uncemented sand below to crumble away. The resulting caves and honeycomb formations are called tafoni.
There are three areas in the Santa Cruz Mountains, all off of Skyline Boulevard (Highway 35,) that are particularly known for their tafoni. The most well known is at Castle Rock State Park. The sandstone here is hard enough that climbing is allowed and on 80-foot high sandstone outcropping is particularly popular.
Across Skyline Boulevard from Castle Rock in Sanborn County Park their is Summit Rock. With an elevation of 3076 feet you can take in the tafoni along with a nice panorama view of the Silicon Valley. On the down side, there is some graffiti on Summit Rock probable. The county parks just aren't as well policed as state parks and the hike is short enough that slobs can find their way to deface this natural beauty.
The third area of noted tafoni is located in the El Corte de Madera Creek Open Space Preserve between Highway 92 and Woodside Road at Skegg's Point Caltrans Rest Stop. The rock is only 2.5 mile hike from Highway 35. However, the bad guys haven't discovered this area yet so please only tell your responsible friends. There are 33 miles of multi-use trains within this 2,821-acre preserve. The preserve was established to protect the headwaters of the San Gregorio Creek watershed that is critical habitat for steelhead trout and coho salmon. Therefore, certain trails have been closed to the public to enable restoration. Failure of visitors to respect these closures could easily result in the entire preserve being closed to the public. The sandstone at El Corte de Madera Creek is softer and more fragile than at places such as Castle Rock and climbing is not allowed here. The up side of the rock being more fragile is that the tafoni is more spectacular. So, we highly recommend this preserve to our responsible flickr photographer friends. The light at the sandstone is very filtered and I really needed to carry a sturdier tripod (I normally just have a Trekpod) and a strong external flash for flash fill. Next time I'm bringing these items along.
This orange dropped off the tree before fully ripe. When I finally cut it open tonight, I saw that it had a very odd composition.
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Trichocereus often times grow bad and weird in Arizona because of the extreme heat like this plant with mass segmentation. In California they grow BEAUTIFUL.
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Spirit and Opportunity the two Mars rovers launched in 2003 by NASA. Both
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I was a bit thrown buy the body segmentation of this insect as it resembles a beetle I have seen many times but something looks different about it. Any I.D. help much appreciated! ! Found on a bush care site in Katoomba, Blue Mountains, NSW.
New command '-x_minimal_path' available for command line users of G'MIC.
It launches an interactive demo illustrating the use of minimal paths for image segmentation.
Better data is becoming available on economic activity within countries, often much exceeding the available information of economic activity across countries. This creates new research opportunities for testing economic theory, analyzing market structures and the sources of market segmentation, and making predictions of how economic shocks propagate across space. The aim of this conference is to bring together researchers from urban economics, industrial organization, health economics, and international trade to study production and trade within and across countries.
20. November 2019, Jugendstilhörsaal der MedUni Wien
“Multiparametic Diagnostics and Theranostics of Tumors”
Fabian Kiessling, Universitätsklinikum Aachen
Abstract:
Significant advances have been achieved in elucidating molecular regulations of cancer and numerous disease-related markers were identified. Additionally, imaging technologies steadily improved and are providing detailed insight into tissues’ morphology, function and molecular regulation. However, there is still a need to identify and quantify the most relevant information and to bring it into a mechanistic context.
In the first part of my talk, I present advanced imaging strategies to characterize tumors by assessing various “hallmarks of cancer” using non-invasive imaging and to assess therapy responses. In this context, I will discuss novel computer applications to improve data processing, lesion detection and segmentation as well as radiomic image analysis. However, taking a study on hepatocellular carcinoma therapy with a multispecific tyrosine kinase inhibitor as an example, I will also show that correlative analyses do not always lead to correct conclusions on biological mechanisms and that the interconnection and impact of the observed changes need to be understood.
The second part of my talk will be dedicated to drug delivery. Here, I will show how imaging can be used to improve the preselection of patients to therapies and discuss the value of nanomedicines and active targeting. Furthermore, I will highlight the potential of ultrasound mediated theranostics to overcome biological barriers and to improve tumor perfusion.
(c) MedUni Wien / Kovic
playing with some new ideas involving desktop segmentation over time... tracking usage... public information & sharing....
20. November 2019, Jugendstilhörsaal der MedUni Wien
“Multiparametic Diagnostics and Theranostics of Tumors”
Fabian Kiessling, Universitätsklinikum Aachen
Abstract:
Significant advances have been achieved in elucidating molecular regulations of cancer and numerous disease-related markers were identified. Additionally, imaging technologies steadily improved and are providing detailed insight into tissues’ morphology, function and molecular regulation. However, there is still a need to identify and quantify the most relevant information and to bring it into a mechanistic context.
In the first part of my talk, I present advanced imaging strategies to characterize tumors by assessing various “hallmarks of cancer” using non-invasive imaging and to assess therapy responses. In this context, I will discuss novel computer applications to improve data processing, lesion detection and segmentation as well as radiomic image analysis. However, taking a study on hepatocellular carcinoma therapy with a multispecific tyrosine kinase inhibitor as an example, I will also show that correlative analyses do not always lead to correct conclusions on biological mechanisms and that the interconnection and impact of the observed changes need to be understood.
The second part of my talk will be dedicated to drug delivery. Here, I will show how imaging can be used to improve the preselection of patients to therapies and discuss the value of nanomedicines and active targeting. Furthermore, I will highlight the potential of ultrasound mediated theranostics to overcome biological barriers and to improve tumor perfusion.
(c) MedUni Wien / Kovic
20. November 2019, Jugendstilhörsaal der MedUni Wien
“Multiparametic Diagnostics and Theranostics of Tumors”
Fabian Kiessling, Universitätsklinikum Aachen
Abstract:
Significant advances have been achieved in elucidating molecular regulations of cancer and numerous disease-related markers were identified. Additionally, imaging technologies steadily improved and are providing detailed insight into tissues’ morphology, function and molecular regulation. However, there is still a need to identify and quantify the most relevant information and to bring it into a mechanistic context.
In the first part of my talk, I present advanced imaging strategies to characterize tumors by assessing various “hallmarks of cancer” using non-invasive imaging and to assess therapy responses. In this context, I will discuss novel computer applications to improve data processing, lesion detection and segmentation as well as radiomic image analysis. However, taking a study on hepatocellular carcinoma therapy with a multispecific tyrosine kinase inhibitor as an example, I will also show that correlative analyses do not always lead to correct conclusions on biological mechanisms and that the interconnection and impact of the observed changes need to be understood.
The second part of my talk will be dedicated to drug delivery. Here, I will show how imaging can be used to improve the preselection of patients to therapies and discuss the value of nanomedicines and active targeting. Furthermore, I will highlight the potential of ultrasound mediated theranostics to overcome biological barriers and to improve tumor perfusion.
(c) MedUni Wien / Kovic
Segmentation board game
A hands-on, interactive game that allows stakeholders to engage and empathise with their target customers by putting segments into real life situations to explore different scenarios and contexts.
20. November 2019, Jugendstilhörsaal der MedUni Wien
“Multiparametic Diagnostics and Theranostics of Tumors”
Fabian Kiessling, Universitätsklinikum Aachen
Abstract:
Significant advances have been achieved in elucidating molecular regulations of cancer and numerous disease-related markers were identified. Additionally, imaging technologies steadily improved and are providing detailed insight into tissues’ morphology, function and molecular regulation. However, there is still a need to identify and quantify the most relevant information and to bring it into a mechanistic context.
In the first part of my talk, I present advanced imaging strategies to characterize tumors by assessing various “hallmarks of cancer” using non-invasive imaging and to assess therapy responses. In this context, I will discuss novel computer applications to improve data processing, lesion detection and segmentation as well as radiomic image analysis. However, taking a study on hepatocellular carcinoma therapy with a multispecific tyrosine kinase inhibitor as an example, I will also show that correlative analyses do not always lead to correct conclusions on biological mechanisms and that the interconnection and impact of the observed changes need to be understood.
The second part of my talk will be dedicated to drug delivery. Here, I will show how imaging can be used to improve the preselection of patients to therapies and discuss the value of nanomedicines and active targeting. Furthermore, I will highlight the potential of ultrasound mediated theranostics to overcome biological barriers and to improve tumor perfusion.
(c) MedUni Wien / Kovic
Capturing data is at the core of almost all digital health companies, representing unprecedented opportunities. Presumably, health data enables powerful analytics. But how can health analytics directly grow your company beyond improving market segmentation, efficiencies and cost-effectiveness/benefit analyses?
As the consumer market becomes flooded with data and analytics, digital health will level the playing field between consumers and traditional stakeholders in healthcare. This critical master class will discuss how your company can lead digital health and turn transparency into value-add, actionable results to nurture engagement and trust among your ultimate customers – all of us, health consumers.
With over twenty years of experience in academic medicine and scientific research, Dr. Yao will share her vision of how scientific research, IT, and business processes can be integrated to move health analytics from being an efficiency-driver at best to the front line as product offerings to improve health. In her current role as CEO of Univfy, Dr. Yao has led both scientific and business fronts from founding of the company to the launch of health analytics on both consumer and business platforms to international and US customers.
Mylene Yao, MD, Co-founder and CEO,UNIVFY Inc. @MyleneYao
"http://summersummit.digitalhealthsummit.com/ - The Digital Health Summer Summit takes a deep dive into what it takes to build a successful digital health venture. It's a unique opportunity for entrepreneurs (and intrapreneurs) to hear industry veterans and key industry players share their lessons learned and best practices.
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Digital Health Summit Website: bit.ly/DigitalHealthWebsite
Summer Summit Website: bit.ly/DigitalHealthSummer
Twitter: bit.ly/DigitalHealthTwitter
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Linkedin: bit.ly/DigitalHealthLinkedIn
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Google+: bit.ly/DigitalHealthGPlus
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Author: Paula Fernandes
Date: April 2008
Description: The active contour method is a semi-automatic image segmentation process based on deformable models, i.e., closed parametric curves or surfaces with physical properties that, under the influence of external and internal mechanical forces, deform and coalesce adapting to image features. This figure exhibits the active contour evolution of a cervical spine, showing a transversal section of the segmented image data (left) and the corresponding 3-D evolution (right).
Source: Ribeiro, N. S., Fernandes, P. C., Lopes, D. S., Folgado, J. O., Fernandes, P. R., 3-D Solid and Finite Element Modeling of Biomechanical Structures - A Software Pipeline, In: Proceedings of the 7th EUROMECH Solid Mechanics Conference, Portugal, 2009.
Image and caption provided by: Paula Fernandes, IDMEC/IST-TU Lisbon
20. November 2019, Jugendstilhörsaal der MedUni Wien
“Multiparametic Diagnostics and Theranostics of Tumors”
Fabian Kiessling, Universitätsklinikum Aachen
Abstract:
Significant advances have been achieved in elucidating molecular regulations of cancer and numerous disease-related markers were identified. Additionally, imaging technologies steadily improved and are providing detailed insight into tissues’ morphology, function and molecular regulation. However, there is still a need to identify and quantify the most relevant information and to bring it into a mechanistic context.
In the first part of my talk, I present advanced imaging strategies to characterize tumors by assessing various “hallmarks of cancer” using non-invasive imaging and to assess therapy responses. In this context, I will discuss novel computer applications to improve data processing, lesion detection and segmentation as well as radiomic image analysis. However, taking a study on hepatocellular carcinoma therapy with a multispecific tyrosine kinase inhibitor as an example, I will also show that correlative analyses do not always lead to correct conclusions on biological mechanisms and that the interconnection and impact of the observed changes need to be understood.
The second part of my talk will be dedicated to drug delivery. Here, I will show how imaging can be used to improve the preselection of patients to therapies and discuss the value of nanomedicines and active targeting. Furthermore, I will highlight the potential of ultrasound mediated theranostics to overcome biological barriers and to improve tumor perfusion.
(c) MedUni Wien / Kovic
The Silver Lining: An Innovation Playbook for Uncertain Times
Author: Scott D. Anthony
Description: Experts agree: The turbulence triggered by the economic shock of 2008 constitutes the "new normal." Unfortunately, too many managers have become paralyzed by it, capable only of slashing costs indiscriminately.
Though examining spending during recessions makes sense, the smartest executives do much more. As Scott Anthony reveals in The Silver Lining, these leaders continue innovating--by stopping ineffective initiatives, changing key business processes, and starting more productive behaviors. Result? Their companies emerge from downturns stronger than ever.
Providing a wealth of ideas, tools, and examples from diverse industries, Anthony explains how to safeguard your company's profitability during even the toughest recessions. You'll discover how to:
-Prune your innovation and business portfolio to liberate resources for more promising initiatives
- Adopt a radical new market-segmentation scheme that helps you re-feature your offerings to reduce costs while delivering new value to customers
- Reinvent your innovation process to drive fresh growth
- Mitigate innovation risks by conducting strategic experiments and forging alliances with customers and other external entities
- Appeal to increasingly value-conscious customers to fend off low-cost attackers
In today's brutal economic climate, executives must pare costs to the bone while planting and nurturing seeds for tomorrow's growth. The Silver Lining explains how to master this seemingly impossible challenge.
Author Bio: Scott D. Anthony is president of Innosight, an innovation consultancy, and lead author of The Innovator's Guide to Growth: Putting Disruptive Innovation to Work. At Innosight, he has worked with clients ranging from national governments to leading consumer-products, media, health-care, telecommunications, and software companies.
Scott's HBR blog: blogs.hbr.org/anthony/
Other works by Scott:
Innovator's Guide to Growth
Seeing What's Next
Spotting Constraints on Consumption
Prioritizing Assumptions and Risks
The Importance of Understanding Your Customers
Contact: publicity@hbr.org
The Brown Wired Stonefly is certainly one of the most lifelike and effective stoneflies available. The two color segmentation and durablility of the wire body make this a favorite among stonefly nymphs. The fact that big fish find this pattern irresistable only adds to its appeal. Every fly fisher should have a few of these ready to go when its stonefly time.
Cikuan Bra fishtail wedding, suffused with a soft sheen satin belt with good visual segmentation add layering, simple fishtail skirt lined sketched out the bride graceful posture, nestled in the tissue, akinds of the looming beauty, particularly sultry.
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Spiders (order Araneae) are air-breathing arthropods that have eight legs and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other orders of organisms. Spiders are found worldwide on every continent except for Antarctica, and have become established in nearly every habitat with the exceptions of air and sea colonization. As of November 2015, at least 45,700 spider species, and 114 families have been recorded by taxonomists. However, there has been dissension within the scientific community as to how all these families should be classified, as evidenced by the over 20 different classifications that have been proposed since 1900.
Anatomically, spiders differ from other arthropods in that the usual body segments are fused into two tagmata, the cephalothorax and abdomen, and joined by a small, cylindrical pedicel. Unlike insects, spiders do not have antennae. In all except the most primitive group, the Mesothelae, spiders have the most centralized nervous systems of all arthropods, as all their ganglia are fused into one mass in the cephalothorax. Unlike most arthropods, spiders have no extensor muscles in their limbs and instead extend them by hydraulic pressure.
Their abdomens bear appendages that have been modified into spinnerets that extrude silk from up to six types of glands. Spider webs vary widely in size, shape and the amount of sticky thread used. It now appears that the spiral orb web may be one of the earliest forms, and spiders that produce tangled cobwebs are more abundant and diverse than orb-web spiders. Spider-like arachnids with silk-producing spigots appeared in the Devonian period about 386 million years ago, but these animals apparently lacked spinnerets. True spiders have been found in Carboniferous rocks from 318 to 299 million years ago, and are very similar to the most primitive surviving suborder, the Mesothelae. The main groups of modern spiders, Mygalomorphae and Araneomorphae, first appeared in the Triassic period, before 200 million years ago.
A herbivorous species, Bagheera kiplingi, was described in 2008, but all other known species are predators, mostly preying on insects and on other spiders, although a few large species also take birds and lizards. Spiders use a wide range of strategies to capture prey: trapping it in sticky webs, lassoing it with sticky bolas, mimicking the prey to avoid detection, or running it down. Most detect prey mainly by sensing vibrations, but the active hunters have acute vision, and hunters of the genus Portia show signs of intelligence in their choice of tactics and ability to develop new ones. Spiders' guts are too narrow to take solids, and they liquefy their food by flooding it with digestive enzymes and grinding it with the bases of their pedipalps, as they do not have true jaws.
Male spiders identify themselves by a variety of complex courtship rituals to avoid being eaten by the females. Males of most species survive a few matings, limited mainly by their short life spans. Females weave silk egg-cases, each of which may contain hundreds of eggs. Females of many species care for their young, for example by carrying them around or by sharing food with them. A minority of species are social, building communal webs that may house anywhere from a few to 50,000 individuals. Social behavior ranges from precarious toleration, as in the widow spiders, to co-operative hunting and food-sharing. Although most spiders live for at most two years, tarantulas and other mygalomorph spiders can live up to 25 years in captivity.
While the venom of a few species is dangerous to humans, scientists are now researching the use of spider venom in medicine and as non-polluting pesticides. Spider silk provides a combination of lightness, strength and elasticity that is superior to that of synthetic materials, and spider silk genes have been inserted into mammals and plants to see if these can be used as silk factories. As a result of their wide range of behaviors, spiders have become common symbols in art and mythology symbolizing various combinations of patience, cruelty and creative powers. An abnormal fear of spiders is called arachnophobia.
DESCRIPTION
BODY PLAN
Spiders are chelicerates and therefore arthropods. As arthropods they have: segmented bodies with jointed limbs, all covered in a cuticle made of chitin and proteins; heads that are composed of several segments that fuse during the development of the embryo.[7] Being chelicerates, their bodies consist of two tagmata, sets of segments that serve similar functions: the foremost one, called the cephalothorax or prosoma, is a complete fusion of the segments that in an insect would form two separate tagmata, the head and thorax; the rear tagma is called the abdomen or opisthosoma. In spiders, the cephalothorax and abdomen are connected by a small cylindrical section, the pedicel. The pattern of segment fusion that forms chelicerates' heads is unique among arthropods, and what would normally be the first head segment disappears at an early stage of development, so that chelicerates lack the antennae typical of most arthropods. In fact, chelicerates' only appendages ahead of the mouth are a pair of chelicerae, and they lack anything that would function directly as "jaws". The first appendages behind the mouth are called pedipalps, and serve different functions within different groups of chelicerates.
Spiders and scorpions are members of one chelicerate group, the arachnids. Scorpions' chelicerae have three sections and are used in feeding. Spiders' chelicerae have two sections and terminate in fangs that are generally venomous, and fold away behind the upper sections while not in use. The upper sections generally have thick "beards" that filter solid lumps out of their food, as spiders can take only liquid food. Scorpions' pedipalps generally form large claws for capturing prey, while those of spiders are fairly small appendages whose bases also act as an extension of the mouth; in addition, those of male spiders have enlarged last sections used for sperm transfer.
In spiders, the cephalothorax and abdomen are joined by a small, cylindrical pedicel, which enables the abdomen to move independently when producing silk. The upper surface of the cephalothorax is covered by a single, convex carapace, while the underside is covered by two rather flat plates. The abdomen is soft and egg-shaped. It shows no sign of segmentation, except that the primitive Mesothelae, whose living members are the Liphistiidae, have segmented plates on the upper surface.
Like other arthropods, spiders are coelomates in which the coelom is reduced to small areas round the reproductive and excretory systems. Its place is largely taken by a hemocoel, a cavity that runs most of the length of the body and through which blood flows. The heart is a tube in the upper part of the body, with a few ostia that act as non-return valves allowing blood to enter the heart from the hemocoel but prevent it from leaving before it reaches the front end. However, in spiders, it occupies only the upper part of the abdomen, and blood is discharged into the hemocoel by one artery that opens at the rear end of the abdomen and by branching arteries that pass through the pedicle and open into several parts of the cephalothorax. Hence spiders have open circulatory systems. The blood of many spiders that have book lungs contains the respiratory pigment hemocyanin to make oxygen transport more efficient.
Spiders have developed several different respiratory anatomies, based on book lungs, a tracheal system, or both. Mygalomorph and Mesothelae spiders have two pairs of book lungs filled with haemolymph, where openings on the ventral surface of the abdomen allow air to enter and diffuse oxygen. This is also the case for some basal araneomorph spiders, like the family Hypochilidae, but the remaining members of this group have just the anterior pair of book lungs intact while the posterior pair of breathing organs are partly or fully modified into tracheae, through which oxygen is diffused into the haemolymph or directly to the tissue and organs. The trachea system has most likely evolved in small ancestors to help resist desiccation. The trachea were originally connected to the surroundings through a pair of openings called spiracles, but in the majority of spiders this pair of spiracles has fused into a single one in the middle, and moved backwards close to the spinnerets. Spiders that have tracheae generally have higher metabolic rates and better water conservation. Spiders are ectotherms, so environmental temperatures affect their activity.
FEEDING, DIGESTION AND EXCRETION
Uniquely among chelicerates, the final sections of spiders' chelicerae are fangs, and the great majority of spiders can use them to inject venom into prey from venom glands in the roots of the chelicerae. The family Uloboridae has lost its venom glands, and kills its prey with silk instead. Like most arachnids, including scorpions, spiders have a narrow gut that can only cope with liquid food and spiders have two sets of filters to keep solids out. They use one of two different systems of external digestion. Some pump digestive enzymes from the midgut into the prey and then suck the liquified tissues of the prey into the gut, eventually leaving behind the empty husk of the prey. Others grind the prey to pulp using the chelicerae and the bases of the pedipalps, while flooding it with enzymes; in these species, the chelicerae and the bases of the pedipalps form a preoral cavity that holds the food they are processing.
The stomach in the cephalothorax acts as a pump that sends the food deeper into the digestive system. The mid gut bears many digestive ceca, compartments with no other exit, that extract nutrients from the food; most are in the abdomen, which is dominated by the digestive system, but a few are found in the cephalothorax.
Most spiders convert nitrogenous waste products into uric acid, which can be excreted as a dry material. Malphigian tubules ("little tubes") extract these wastes from the blood in the hemocoel and dump them into the cloacal chamber, from which they are expelled through the anus. Production of uric acid and its removal via Malphigian tubules are a water-conserving feature that has evolved independently in several arthropod lineages that can live far away from water,[14] for example the tubules of insects and arachnids develop from completely different parts of the embryo. However, a few primitive spiders, the sub-order Mesothelae and infra-order Mygalomorphae, retain the ancestral arthropod nephridia ("little kidneys"), which use large amounts of water to excrete nitrogenous waste products as ammonia.
CENTRAL NERVOS SYSTEM
The basic arthropod central nervous system consists of a pair of nerve cords running below the gut, with paired ganglia as local control centers in all segments; a brain formed by fusion of the ganglia for the head segments ahead of and behind the mouth, so that the esophagus is encircled by this conglomeration of ganglia. Except for the primitive Mesothelae, of which the Liphistiidae are the sole surviving family, spiders have the much more centralized nervous system that is typical of arachnids: all the ganglia of all segments behind the esophagus are fused, so that the cephalothorax is largely filled with nervous tissue and there are no ganglia in the abdomen; in the Mesothelae, the ganglia of the abdomen and the rear part of the cephalothorax remain unfused.
Despite the relatively small central nervous system, some spiders (like Portia) exhibit complex behaviour, including the ability to use a trial-and-error approach.
SENSE ORGANS
EYES
Most spiders have four pairs of eyes on the top-front area of the cephalothorax, arranged in patterns that vary from one family to another. The pair at the front are of the type called pigment-cup ocelli ("little eyes"), which in most arthropods are only capable of detecting the direction from which light is coming, using the shadow cast by the walls of the cup. However, the main eyes at the front of spiders' heads are pigment-cup ocelli that are capable of forming images. The other eyes are thought to be derived from the compound eyes of the ancestral chelicerates, but no longer have the separate facets typical of compound eyes. Unlike the main eyes, in many spiders these secondary eyes detect light reflected from a reflective tapetum lucidum, and wolf spiders can be spotted by torch light reflected from the tapeta. On the other hand, jumping spiders' secondary eyes have no tapeta. Some jumping spiders' visual acuity exceeds by a factor of ten that of dragonflies, which have by far the best vision among insects; in fact the human eye is only about five times sharper than a jumping spider's. They achieve this by a telephoto-like series of lenses, a four-layer retina and the ability to swivel their eyes and integrate images from different stages in the scan. The downside is that the scanning and integrating processes are relatively slow.
There are spiders with a reduced number of eyes, of these those with six-eyes are the most numerous and are missing a pair of eyes on the anterior median line, others species have four-eyes and some just two. Cave dwelling species have no eyes, or possess vestigial eyes incapable of sight.
OTHER SENSES
As with other arthropods, spiders' cuticles would block out information about the outside world, except that they are penetrated by many sensors or connections from sensors to the nervous system. In fact, spiders and other arthropods have modified their cuticles into elaborate arrays of sensors. Various touch sensors, mostly bristles called setae, respond to different levels of force, from strong contact to very weak air currents. Chemical sensors provide equivalents of taste and smell, often by means of setae. Pedipalps carry a large number of such setae sensitive to contact chemicals and air-borne smells, such as female pheromones. Spiders also have in the joints of their limbs slit sensillae that detect forces and vibrations. In web-building spiders, all these mechanical and chemical sensors are more important than the eyes, while the eyes are most important to spiders that hunt actively.
Like most arthropods, spiders lack balance and acceleration sensors and rely on their eyes to tell them which way is up. Arthropods' proprioceptors, sensors that report the force exerted by muscles and the degree of bending in the body and joints, are well understood. On the other hand, little is known about what other internal sensors spiders or other arthropods may have.
LOCOMOTION
Each of the eight legs of a spider consists of seven distinct parts. The part closest to and attaching the leg to the cephalothorax is the coxa; the next segment is the short trochanter that works as a hinge for the following long segment, the femur; next is the spider's knee, the patella, which acts as the hinge for the tibia; the metatarsus is next, and it connects the tibia to the tarsus (which may be thought of as a foot of sorts); the tarsus ends in a claw made up of either two or three points, depending on the family to which the spider belongs. Although all arthropods use muscles attached to the inside of the exoskeleton to flex their limbs, spiders and a few other groups still use hydraulic pressure to extend them, a system inherited from their pre-arthropod ancestors. The only extensor muscles in spider legs are located in the three hip joints (bordering the coxa and the trochanter). As a result, a spider with a punctured cephalothorax cannot extend its legs, and the legs of dead spiders curl up. Spiders can generate pressures up to eight times their resting level to extend their legs, and jumping spiders can jump up to 50 times their own length by suddenly increasing the blood pressure in the third or fourth pair of legs. Although larger spiders use hydraulics to straighten their legs, unlike smaller jumping spiders they depend on their flexor muscles to generate the propulsive force for their jumps.
Most spiders that hunt actively, rather than relying on webs, have dense tufts of fine hairs between the paired claws at the tips of their legs. These tufts, known as scopulae, consist of bristles whose ends are split into as many as 1,000 branches, and enable spiders with scopulae to walk up vertical glass and upside down on ceilings. It appears that scopulae get their grip from contact with extremely thin layers of water on surfaces. Spiders, like most other arachnids, keep at least four legs on the surface while walking or running.
SILK PRODUCTION
The abdomen has no appendages except those that have been modified to form one to four (usually three) pairs of short, movable spinnerets, which emit silk. Each spinneret has many spigots, each of which is connected to one silk gland. There are at least six types of silk gland, each producing a different type of silk.
Silk is mainly composed of a protein very similar to that used in insect silk. It is initially a liquid, and hardens not by exposure to air but as a result of being drawn out, which changes the internal structure of the protein. It is similar in tensile strength to nylon and biological materials such as chitin, collagen and cellulose, but is much more elastic. In other words, it can stretch much further before breaking or losing shape.
Some spiders have a cribellum, a modified spinneret with up to 40,000 spigots, each of which produces a single very fine fiber. The fibers are pulled out by the calamistrum, a comb-like set of bristles on the jointed tip of the cribellum, and combined into a composite woolly thread that is very effective in snagging the bristles of insects. The earliest spiders had cribella, which produced the first silk capable of capturing insects, before spiders developed silk coated with sticky droplets. However, most modern groups of spiders have lost the cribellum.
Tarantulas also have silk glands in their feet.
Even species that do not build webs to catch prey use silk in several ways: as wrappers for sperm and for fertilized eggs; as a "safety rope"; for nest-building; and as "parachutes" by the young of some species.
REPRODUCTION AND LIFE CYCLE
Spiders reproduce sexually and fertilization is internal but indirect, in other words the sperm is not inserted into the female's body by the male's genitals but by an intermediate stage. Unlike many land-living arthropods, male spiders do not produce ready-made spermatophores (packages of sperm), but spin small sperm webs on to which they ejaculate and then transfer the sperm to special syringe-like structures, palpal bulbs or palpal organs, borne on the tips of the pedipalps of mature males. When a male detects signs of a female nearby he checks whether she is of the same species and whether she is ready to mate; for example in species that produce webs or "safety ropes", the male can identify the species and sex of these objects by "smell".
Spiders generally use elaborate courtship rituals to prevent the large females from eating the small males before fertilization, except where the male is so much smaller that he is not worth eating. In web-weaving species, precise patterns of vibrations in the web are a major part of the rituals, while patterns of touches on the female's body are important in many spiders that hunt actively, and may "hypnotize" the female. Gestures and dances by the male are important for jumping spiders, which have excellent eyesight. If courtship is successful, the male injects his sperm from the palpal bulbs into the female's genital opening, known as the epigyne, on the underside of her abdomen. Female's reproductive tracts vary from simple tubes to systems that include seminal receptacles in which females store sperm and release it when they are ready.
Males of the genus Tidarren amputate one of their palps before maturation and enter adult life with one palp only. The palps are 20% of male's body mass in this species, and detaching one of the two improves mobility. In the Yemeni species Tidarren argo, the remaining palp is then torn off by the female. The separated palp remains attached to the female's epigynum for about four hours and apparently continues to function independently. In the meantime, the female feeds on the palpless male. In over 60% of cases, the female of the Australian redback spider kills and eats the male after it inserts its second palp into the female's genital opening; in fact, the males co-operate by trying to impale themselves on the females' fangs. Observation shows that most male redbacks never get an opportunity to mate, and the "lucky" ones increase the likely number of offspring by ensuring that the females are well-fed. However, males of most species survive a few matings, limited mainly by their short life spans. Some even live for a while in their mates' webs.
Females lay up to 3,000 eggs in one or more silk egg sacs, which maintain a fairly constant humidity level. In some species, the females die afterwards, but females of other species protect the sacs by attaching them to their webs, hiding them in nests, carrying them in the chelicerae or attaching them to the spinnerets and dragging them along.
Baby spiders pass all their larval stages inside the egg and hatch as spiderlings, very small and sexually immature but similar in shape to adults. Some spiders care for their young, for example a wolf spider's brood cling to rough bristles on the mother's back, and females of some species respond to the "begging" behaviour of their young by giving them their prey, provided it is no longer struggling, or even regurgitate food.
Like other arthropods, spiders have to molt to grow as their cuticle ("skin") cannot stretch. In some species males mate with newly molted females, which are too weak to be dangerous to the males. Most spiders live for only one to two years, although some tarantulas can live in captivity for over 20 years.
SIZE
Spiders occur in a large range of sizes. The smallest, Patu digua from Colombia, are less than 0.37 mm in body length. The largest and heaviest spiders occur among tarantulas, which can have body lengths up to 90 mm and leg spans up to 250 mm.
ECOLOGY AND BEHAVIOR
NON-PREDATORY FEEDING
Although spiders are generally regarded as predatory, the jumping spider Bagheera kiplingi gets over 90% of its food from fairly solid plant material produced by acacias as part of a mutually beneficial relationship with a species of ant.
Juveniles of some spiders in the families Anyphaenidae, Corinnidae, Clubionidae, Thomisidae and Salticidae feed on plant nectar. Laboratory studies show that they do so deliberately and over extended periods, and periodically clean themselves while feeding. These spiders also prefer sugar solutions to plain water, which indicates that they are seeking nutrients. Since many spiders are nocturnal, the extent of nectar consumption by spiders may have been underestimated. Nectar contains amino acids, lipids, vitamins and minerals in addition to sugars, and studies have shown that other spider species live longer when nectar is available. Feeding on nectar avoids the risks of struggles with prey, and the costs of producing venom and digestive enzymes.
Various species are known to feed on dead arthropods (scavenging), web silk, and their own shed exoskeletons. Pollen caught in webs may also be eaten, and studies have shown that young spiders have a better chance of survival if they have the opportunity to eat pollen. In captivity, several spider species are also known to feed on bananas, marmalade, milk, egg yolk and sausages.
METHODS OF CAPTURING PREY
The best-known method of prey capture is by means of sticky webs. Varying placement of webs allows different species of spider to trap different insects in the same area, for example flat horizontal webs trap insects that fly up from vegetation underneath while flat vertical webs trap insects in horizontal flight. Web-building spiders have poor vision, but are extremely sensitive to vibrations.
Females of the water spider Argyroneta aquatica build underwater "diving bell" webs that they fill with air and use for digesting prey, molting, mating and raising offspring. They live almost entirely within the bells, darting out to catch prey animals that touch the bell or the threads that anchor it. A few spiders use the surfaces of lakes and ponds as "webs", detecting trapped insects by the vibrations that these cause while struggling.
Net-casting spiders weave only small webs, but then manipulate them to trap prey. Those of the genus Hyptiotes and the family Theridiosomatidae stretch their webs and then release them when prey strike them, but do not actively move their webs. Those of the family Deinopidae weave even smaller webs, hold them outstretched between their first two pairs of legs, and lunge and push the webs as much as twice their own body length to trap prey, and this move may increase the webs' area by a factor of up to ten. Experiments have shown that Deinopis spinosus has two different techniques for trapping prey: backwards strikes to catch flying insects, whose vibrations it detects; and forward strikes to catch ground-walking prey that it sees. These two techniques have also been observed in other deinopids. Walking insects form most of the prey of most deinopids, but one population of Deinopis subrufa appears to live mainly on tipulid flies that they catch with the backwards strike.
Mature female bolas spiders of the genus Mastophora build "webs" that consist of only a single "trapeze line", which they patrol. They also construct a bolas made of a single thread, tipped with a large ball of very wet sticky silk. They emit chemicals that resemble the pheromones of moths, and then swing the bolas at the moths. Although they miss on about 50% of strikes, they catch about the same weight of insects per night as web-weaving spiders of similar size. The spiders eat the bolas if they have not made a kill in about 30 minutes, rest for a while, and then make new bolas. Juveniles and adult males are much smaller and do not make bolas. Instead they release different pheromones that attract moth flies, and catch them with their front pairs of legs.
The primitive Liphistiidae, the "trapdoor spiders" of the family Ctenizidae and many tarantulas are ambush predators that lurk in burrows, often closed by trapdoors and often surrounded by networks of silk threads that alert these spiders to the presence of prey. Other ambush predators do without such aids, including many crab spiders, and a few species that prey on bees, which see ultraviolet, can adjust their ultraviolet reflectance to match the flowers in which they are lurking. Wolf spiders, jumping spiders, fishing spiders and some crab spiders capture prey by chasing it, and rely mainly on vision to locate prey.Some jumping spiders of the genus Portia hunt other spiders in ways that seem intelligent, outflanking their victims or luring them from their webs. Laboratory studies show that Portia's instinctive tactics are only starting points for a trial-and-error approach from which these spiders learn very quickly how to overcome new prey species. However, they seem to be relatively slow "thinkers", which is not surprising, as their brains are vastly smaller than those of mammalian predators.
Ant-mimicking spiders face several challenges: they generally develop slimmer abdomens and false "waists" in the cephalothorax to mimic the three distinct regions (tagmata) of an ant's body; they wave the first pair of legs in front of their heads to mimic antennae, which spiders lack, and to conceal the fact that they have eight legs rather than six; they develop large color patches round one pair of eyes to disguise the fact that they generally have eight simple eyes, while ants have two compound eyes; they cover their bodies with reflective hairs to resemble the shiny bodies of ants. In some spider species, males and females mimic different ant species, as female spiders are usually much larger than males. Ant-mimicking spiders also modify their behavior to resemble that of the target species of ant; for example, many adopt a zig-zag pattern of movement, ant-mimicking jumping spiders avoid jumping, and spiders of the genus Synemosyna walk on the outer edges of leaves in the same way as Pseudomyrmex. Ant-mimicry in many spiders and other arthropods may be for protection from predators that hunt by sight, including birds, lizards and spiders. However, several ant-mimicking spiders prey either on ants or on the ants' "livestock", such as aphids. When at rest, the ant-mimicking crab spider Amyciaea does not closely resemble Oecophylla, but while hunting it imitates the behavior of a dying ant to attract worker ants. After a kill, some ant-mimicking spiders hold their victims between themselves and large groups of ants to avoid being attacked.
DEFENSE
There is strong evidence that spiders' coloration is camouflage that helps them to evade their major predators, birds and parasitic wasps, both of which have good color vision. Many spider species are colored so as to merge with their most common backgrounds, and some have disruptive coloration, stripes and blotches that break up their outlines. In a few species, such as the Hawaiian happy-face spider, Theridion grallator, several coloration schemes are present in a ratio that appears to remain constant, and this may make it more difficult for predators to recognize the species. Most spiders are insufficiently dangerous or unpleasant-tasting for warning coloration to offer much benefit. However, a few species with powerful venoms, large jaws or irritant hairs have patches of warning colors, and some actively display these colors when threatened.
Many of the family Theraphosidae, which includes tarantulas and baboon spiders, have urticating hairs on their abdomens and use their legs to flick them at attackers. These hairs are fine setae (bristles) with fragile bases and a row of barbs on the tip. The barbs cause intense irritation but there is no evidence that they carry any kind of venom. A few defend themselves against wasps by including networks of very robust threads in their webs, giving the spider time to flee while the wasps are struggling with the obstacles. The golden wheeling spider, Carparachne aureoflava, of the Namibian desert escapes parasitic wasps by flipping onto its side and cartwheeling down sand dunes.
SOZIAL SPIDERS
A few spider species that build webs live together in large colonies and show social behavior, although not as complex as in social insects. Anelosimus eximius (in the family Theridiidae) can form colonies of up to 50,000 individuals. The genus Anelosimus has a strong tendency towards sociality: all known American species are social, and species in Madagascar are at least somewhat social. Members of other species in the same family but several different genera have independently developed social behavior. For example, although Theridion nigroannulatum belongs to a genus with no other social species, T. nigroannulatum build colonies that may contain several thousand individuals that co-operate in prey capture and share food. Other communal spiders include several Philoponella species (family Uloboridae), Agelena consociata (family Agelenidae) and Mallos gregalis (family Dictynidae). Social predatory spiders need to defend their prey against kleptoparasites ("thieves"), and larger colonies are more successful in this. The herbivorous spider Bagheera kiplingi lives in small colonies which help to protect eggs and spiderlings. Even widow spiders (genus Latrodectus), which are notoriously cannibalistic, have formed small colonies in captivity, sharing webs and feeding together.
WEB TYPES
There is no consistent relationship between the classification of spiders and the types of web they build: species in the same genus may build very similar or significantly different webs. Nor is there much correspondence between spiders' classification and the chemical composition of their silks. Convergent evolution in web construction, in other words use of similar techniques by remotely related species, is rampant. Orb web designs and the spinning behaviors that produce them are the best understood. The basic radial-then-spiral sequence visible in orb webs and the sense of direction required to build them may have been inherited from the common ancestors of most spider groups. However, the majority of spiders build non-orb webs. It used to be thought that the sticky orb web was an evolutionary innovation resulting in the diversification of the Orbiculariae. Now, however, it appears that non-orb spiders are a sub-group that evolved from orb-web spiders, and non-orb spiders have over 40% more species and are four times as abundant as orb-web spiders. Their greater success may be because sphecid wasps, which are often the dominant predators of spiders, much prefer to attack spiders that have flat webs.
ORB WEBS
About half the potential prey that hit orb webs escape. A web has to perform three functions: intercepting the prey (intersection), absorbing its momentum without breaking (stopping), and trapping the prey by entangling it or sticking to it (retention). No single design is best for all prey. For example: wider spacing of lines will increase the web's area and hence its ability to intercept prey, but reduce its stopping power and retention; closer spacing, larger sticky droplets and thicker lines would improve retention, but would make it easier for potential prey to see and avoid the web, at least during the day. However, there are no consistent differences between orb webs built for use during the day and those built for use at night. In fact, there is no simple relationship between orb web design features and the prey they capture, as each orb-weaving species takes a wide range of prey.
The hubs of orb webs, where the spiders lurk, are usually above the center, as the spiders can move downwards faster than upwards. If there is an obvious direction in which the spider can retreat to avoid its own predators, the hub is usually offset towards that direction.
Horizontal orb webs are fairly common, despite being less effective at intercepting and retaining prey and more vulnerable to damage by rain and falling debris. Various researchers have suggested that horizontal webs offer compensating advantages, such as reduced vulnerability to wind damage; reduced visibility to prey flying upwards, because of the back-lighting from the sky; enabling oscillations to catch insects in slow horizontal flight. However, there is no single explanation for the common use of horizontal orb webs.
Spiders often attach highly visible silk bands, called decorations or stabilimenta, to their webs. Field research suggests that webs with more decorative bands captured more prey per hour. However, a laboratory study showed that spiders reduce the building of these decorations if they sense the presence of predators.
In 1973, Skylab 3 took two orb-web spiders into space to test their web-spinning capabilities in zero gravity. At first, both produced rather sloppy webs, but they adapted quickly.
Tangleweb spiders (cobweb spiders)
Members of the family Theridiidae weave irregular, tangled, three-dimensional webs, popularly known as cobwebs. There seems to be an evolutionary trend towards a reduction in the amount of sticky silk used, leading to its total absence in some species. The construction of cobwebs is less stereotyped than that of orb-webs, and may take several days.
OTHER TYPES OF WEBS
The Linyphiidae generally make horizontal but uneven sheets, with tangles of stopping threads above. Insects that hit the stopping threads fall onto the sheet or are shaken onto it by the spider, and are held by sticky threads on the sheet until the spider can attack from below.
EVOLUTION
FOSSIL RECORD
Although the fossil record of spiders is considered poor, almost 1000 species have been described from fossils. Because spiders' bodies are quite soft, the vast majority of fossil spiders have been found preserved in amber. The oldest known amber that contains fossil arthropods dates from 130 million years ago in the Early Cretaceous period. In addition to preserving spiders' anatomy in very fine detail, pieces of amber show spiders mating, killing prey, producing silk and possibly caring for their young. In a few cases, amber has preserved spiders' egg sacs and webs, occasionally with prey attached; the oldest fossil web found so far is 100 million years old. Earlier spider fossils come from a few lagerstätten, places where conditions were exceptionally suited to preserving fairly soft tissues.
The oldest known exclusively terrestrial arachnid is the trigonotarbid Palaeotarbus jerami, from about 420 million years ago in the Silurian period, and had a triangular cephalothorax and segmented abdomen, as well as eight legs and a pair of pedipalps. Attercopus fimbriunguis, from 386 million years ago in the Devonian period, bears the earliest known silk-producing spigots, and was therefore hailed as a spider at the time of its discovery. However, these spigots may have been mounted on the underside of the abdomen rather than on spinnerets, which are modified appendages and whose mobility is important in the building of webs. Hence Attercopus and the similar Permian arachnid Permarachne may not have been true spiders, and probably used silk for lining nests or producing egg-cases rather than for building webs. The largest known fossil spider as of 2011 is the araneid Nephila jurassica, from about 165 million years ago, recorded from Daohuogo, Inner Mongolia in China. Its body length is almost 25 mm.
Several Carboniferous spiders were members of the Mesothelae, a primitive group now represented only by the Liphistiidae. The mesothelid Paleothele montceauensis, from the Late Carboniferous over 299 million years ago, had five spinnerets. Although the Permian period 299 to 251 million years ago saw rapid diversification of flying insects, there are very few fossil spiders from this period.
The main groups of modern spiders, Mygalomorphae and Araneomorphae, first appear in the Triassic well before 200 million years ago. Some Triassic mygalomorphs appear to be members of the family Hexathelidae, whose modern members include the notorious Sydney funnel-web spider, and their spinnerets appear adapted for building funnel-shaped webs to catch jumping insects. Araneomorphae account for the great majority of modern spiders, including those that weave the familiar orb-shaped webs. The Jurassic and Cretaceous periods provide a large number of fossil spiders, including representatives of many modern families.
FAMILY TREE
It is now agreed that spiders (Araneae) are monophyletic (i.e., members of a group of organisms that form a clade, consisting of a last common ancestor and all of its descendants). There has been debate about what their closest evolutionary relatives are, and how all of these evolved from the ancestral chelicerates, which were marine animals. The cladogram on the right is based on J. W. Shultz' analysis (2007). Other views include proposals that: scorpions are more closely related to the extinct marine scorpion-like eurypterids than to spiders; spiders and Amblypygi are a monophyletic group. The appearance of several multi-way branchings in the tree on the right shows that there are still uncertainties about relationships between the groups involved.
Arachnids lack some features of other chelicerates, including backward-pointing mouths and gnathobases ("jaw bases") at the bases of their legs; both of these features are part of the ancestral arthropod feeding system. Instead, they have mouths that point forwards and downwards, and all have some means of breathing air. Spiders (Araneae) are distinguished from other arachnid groups by several characteristics, including spinnerets and, in males, pedipalps that are specially adapted for sperm transfer.
TAXONOMY
Spiders are divided into two suborders, Mesothelae and Opisthothelae, of which the latter contains two infraorders, Mygalomorphae and Araneomorphae. Nearly 46,000 living species of spiders (order Araneae) have been identified and are currently grouped into about 114 families and about 4,000 genera by arachnologists.
WIKIPEDIA
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This is a very interesting piece emphasizing Koreans' cultural and political identity. Last year there had been a dispute over the official Chinese name Hancheng （汉城） for the South Korean capital Seoul. In this ad (to be found in many underground stations in the capital) it is announced that at last the name in Chinese has been changed to the sound translation Shou'er （首尔）.
On the left you can see a white guy (representative for all Western countries), a Japanese lady and a Chinese, the latter shaking a Korean's hand, having finally established friendship by pronouncing the South Korean capital's name correctly and not using a historically wrong name.
"Seoul （首尔）, the first city / The Chinese designation for Seoul is 首尔 (Seoul) / Now in China, too, Seoul is being called Shou'er"
I sometimes have a similar problem when after the 1988 Olympics and the 2002 Soccer Worldcup some westerners still cannot seem to get it right. Some Germans for instance don't realize that the name consists of the two syllables Seo-ul and there is no segmentation between the 'e' and the 'o'. A people who also commit a terrible phonetic sin here are the French. They even use an accent and say Sé-oul which underlines how convinced they are that they are in the right :)
I wonder if they will eventually express their displeasure about that in Seoul... Maybe not – Europe is too far away.
(Further pictures you can see quite easily by clicking on the link at the end of page!)
Vienna 1, The Franciscan Church
The Franciscans go back to St. Francis of Assisi and thus the 13th Century. They were founded as a mendicant orders but soon the arose the question how literally one should take the declaration of poverty. Was it allowed to make financial provision for elderly or sick brothers? Finally it came to the segmentation of the faith community, the more liberal Minoriten (Friars Minor Conventual) made their own order, while the Franciscans followed the old conventions. 1453 came the first Franciscan, John of Capistrano, to Vienna.
He founded the first Franciscan monastery in what is now 6th District. But the monks had to flee when the Turks besieged Vienna in 1529 and the monastery burned down. It took until 1589 until the city of Vienna gave them the at that time vacant monastery together with appendant church. The house, in its place now stands the monastery had already been donated in 1306 by wealthy citizens - namely for "loose women" who wanted give up their trade and convert themselves.
1476 was at the Weichenburg (hence Weihburggasse) inaugurated a church with seven altars, where formerly a "Pfarrheusl (small parsonage)" had stood for the soul welfare of the female residents. At the time of the Reformation, however, moral values in this house went downhill. 1553, the Foundation was dissolved, but it took yet until 1572 before the last resident had died. For eight years, the building was then an educational establishment for girls of poor people.
When the Franciscans now had got the property, they started in 1603 with a reconstruction of the church, which was consecrated in 1611. 1614, the foundation stone was laid for the new monastery.
The statues on the west facade are left Francis of Assisi and Anthony of Padua right. In the middle, on the pediment of the west portal of the Church stands Jerome, protector of the church. He is surrounded by two angle putti.
But let's go inside the church. Maria with the ax is the altarpiece above the high altar. The statue was carved in 1505 from lime wood and has its own story. She comes from the Green Mountain (Grünberg) in Bohemia, which was under the control the Sternberg family. Since the family in the meantime had become Protestant, it wanted to burn the statue. She were thrown into the fire - but the next day she stood unharmed again in the chapel. Now, the executioner was called who should dismember the effigy. However, even that was impossible, because the ax stuck in the shoulder of Mary and it was not possible to get it out. There it is still today. (You have to look closely, but then you see the great ax with slightly curved stem.) But that's not enough. A few years later the Madonna was lost in the gamble by a gegenreformierten (counter-reformed) Sternberg. The new owner, the Polish Baron Turnoffsky gave she in 1607 the Franciscan monastery. Exactly 100 years later, she got her current stand on the high altar.
The stone structure between altar and the statue of the Madonna also contains a crucifix, which dates from the beginning of the 17th Century. The wooden statues left and right represent the Saints Jerome respectively Francis and are typical examples of the so-called Franciscan carving school. It operated 1690-1730 and was run by lay brothers. The overall concept for the high altar dates back to the Jesuit Andrea dal Pozzo.
A special attraction is the organ by Hans Wöckherl that was already built in 1642 and today is the oldest organ in Vienna. It is, however, disappeared from the visible church, because it is behind the high altar and is only shown every Friday between 15.00 und 15.30 clock. In addition, one demans for that six euro entry...
The single-nave church has to both sides side chapels, of them I want to show two.
On the left we see the Magdalene Chapel, which was consecrated already in 1614 for the first time. 1644 and 1722, however, followed Neustiftungen (new foundings). The stucco decoration stems from 1644. The paintings in the vault are much more recent, from 1893. The altarpiece depicts the grieving Mary Magdalene under the Cross. It was created in 1725 by Carlo Innocenzo Carlone. The image above shows Veronica's handkerchief with the face of Christ. It was painted by Wolfram Koeberl and in 1974 installed. The statues beside the altar represent the Virgin Mary and John the Baptist. The two above chapels are provided with food grid, so that one could give Communion here.
An Immaculata chapel (pictured above right) is there since the existence of the church, but this was rebuilt in 1722. Previously, since 1642, there was a Michael altar here. From this period dates still the stucco decor on the ceiling. The altarpiece is by Johann Georg Schmidt, who painted it in 1721. The lateral statues depict the Saint Joachim and the mother of Mary.
Also the Capistrano Chapel, which was founded in 1723, is worth mentioning. The lateral stucco decor shows on the left side (picture) the glorification of St. John Capistrano, who, as I said, was the first Franciscan in Vienna. Right you can see him as a standard-bearer of Christian doctrine in the wars against the Turks. Both stucco images date from the time of the foundation. The altarpiece by Franz Xaver Wagenschön originated in 1761 and shows Capistrano in a scene from 1451, in Brescia when he healed a possessed man.
In the picture we see also the statue of Saint George, as he is killing the (admittedly small) dragon.
On the other side of the chapel is the Holy Florian, while Clara and Theresa stand next to the altar. Behind the altar there is a reliquary in glass from about 1720, in which we see a wax image of the Holy Hilaria. The relic shall be imbedded in the wax. Hilaria is rather unknown, but she was a martyr who was converted by Bishop Narcissus. She died in the year 304 in Augsburg, at the behest of the governor Gaius, because she did not want to renounce the Christian faith. About the nature of death, there are different opinions.
In the church there is a plaque that claims that she was burned at the grave of her daughter, while the Holy Encyclopedia states that she was enclosed in her house and this was then set on fire.
In the chapel opposite, the Chapel of the Good Shepherd, there is also a glass coffin with a relic. This is the skeleton of the Felix Puer wearing the uniform of a Roman Centurion.
As a counterpart to the pulpit, this just opposite, you will find the monument of Johann Nepomuk. We see how he flows on the water of the Vltava river after he was thrown in Prague there. He actually was called "John from Nepomuk" in Czech "ne Pomuk". The wife of Emperor Wenceslas IV is said to have chosen him as confessor. The Emperor wanted to know then what she had confessed, but Johann Nepomuk did not betray the seal of confession and was therefore thrown into the water. The Empress had then an appearance of five stars.
(We see she also in the water of the monument.) These stars indicated were one could find the body. So much for the legend.
The fact is that Johann Nepomuk was tortured by the king and thrown into the Vltava. The activating moment was a dispute over a new monastery between the emperor and the archbishop of Prague, in which John Nepomuk was trampled underfoot ...
The pulpit was built in 1726 and was executed by the Franciscan carving school. At the parapet there are wooden reliefs of Matthew, Mark and Luke. The relief of the fourth evangelist, John, is attached to the pulpit door. At the parapet you further can see statues of Capistrano and Bonaventura, while on the sounding board are sitting Anthony of Padua and Berhardin of Siena. At the top stands the freeze image of Francis of Assisi.
The pews were 1727 - 1729 by brother Johann Gottfried Hartmann built and carved.