Next Instar - _TNY_4097
When butterflies lay eggs, they are obviously very small (the eggs - not the butterflies!) so the caterpillars that eventually emerge are also very very small.
As the caterpillar eats (which they pretty much do exclusively) they grow and eventually they quite literally grow out of their skin since the skin doesn't grow with them in the same way ours do.
Their solution is to have the skin burst open and have another, fresh and a bit larger skin to fill out with more food as they keep growing.
These phases are known as instar stages and they go through five of them before turning into a chrysalis and begin the metamorphosis into the adult form, the imago.
Two days ago I posted a shot of a 2nd instar caterpillar of the common yellow swallowtail (Papilio machaon) here: www.flickr.com/photos/tinyturtle/53399838441/ - and here is the very next phase.
When I say "very next", that's no lie. See that black stuff at the tail end of the closer caterpillar? That is in fact the old, 2nd instar, skin which the caterpillar is in the process of climbing out of to continue life as a 3rd instar form..
Next Instar - _TNY_4097
When butterflies lay eggs, they are obviously very small (the eggs - not the butterflies!) so the caterpillars that eventually emerge are also very very small.
As the caterpillar eats (which they pretty much do exclusively) they grow and eventually they quite literally grow out of their skin since the skin doesn't grow with them in the same way ours do.
Their solution is to have the skin burst open and have another, fresh and a bit larger skin to fill out with more food as they keep growing.
These phases are known as instar stages and they go through five of them before turning into a chrysalis and begin the metamorphosis into the adult form, the imago.
Two days ago I posted a shot of a 2nd instar caterpillar of the common yellow swallowtail (Papilio machaon) here: www.flickr.com/photos/tinyturtle/53399838441/ - and here is the very next phase.
When I say "very next", that's no lie. See that black stuff at the tail end of the closer caterpillar? That is in fact the old, 2nd instar, skin which the caterpillar is in the process of climbing out of to continue life as a 3rd instar form..