A little caterpillar anatomy

By DAY 7, the little guys aren't so little anymore...

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Now that we can see some details on these guys, let's learn a little about what we're looking at.


Painted lady caterpillars have three pair of true legs, located closest to the mandible. The remaining five pair are called pro-legs or false legs. Although these 'false legs' are functional and important for the caterpillar for feeding, they get the diss because they are lost during metamorphosis. The butterfly emerges with only three pair of legs.

Each caterpillar has six pair of ocelli, or eyes. Even with all these eyes, their vision is very poor. The structure of the ocelli suggests that caterpillars can not see images, only degrees light and dark. These caterpillars also have chemical detectors for taste and antennae for smell.

The spinneret is the opening of the silk gland, which produces the silk disc to which the chrysalis will attach. The spiracles are pretty cool. More on those later.

A few interesting caterpillar facts:
* Unlike most growing organisms, the number of cells composing the caterpillar body does not increase as the caterpillar grows from newly hatched larva to large caterpillar ready to pupate.

* This is especially impressive when you realize a caterpillar grows to approximately 27,000 times its size from hatchling to pupa. This would be equivalent to a 9 pound human baby growing to 243,000 pounds as an adult. Talk about an obesity crisis!

* Caterpillars have upwards of 4,000 muscles. This doesn't necessarily impress until you remember humans only have 640.

* This terror-inducing rug on a branch is called a woolly slug. It's the most poisonous caterpillar in the United States.


"I'm too sexy for my hair."

That's it for now, but let's check back in on the crew...
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Looks like someone is ready!

More time-lapse coolness:

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