Topic: Wasps (the insect)

[knightstorm]

I'd want robots to do my dirty work too if I had to worry about things like these.

http://www.youtube.com/watch?v=6fTrSOFyfxs

[Bonk]

I'd want robots to do my dirty work too if I had to worry about things like these.
http://www.youtube.com/watch?v=6fTrSOFyfxs

Holy crap! 5x the size of a honey bee? Wow. Incredible camera work there, National Geographic is so awesome, and nature is so cold and hard. Thanks for sharing that clip!

[marstone]

ah but remember.  Starter fluid still melts the exoskeleton even on those big guys. 

[knightstorm]

nature is so cold and hard.

Well, to be fair, those are imported European honey bees with no natural defenses against the Japanese Hornets.  The native Japanese honeybees evolved along side the hornets, and have developed an amazing means of defending themselves, so they fare much better.

http://www.youtube.com/watch?v=R5QxUR-mZVM

ah but remember.  Starter fluid still melts the exoskeleton even on those big guys. 

You get close enough to spray them...  I'll just wait right here.

[Nemesis]

If insects ever develop "lungs" we are doomed.

It appears that they need more than just lungs.

Link to full article

First, a bit of background: Insects don't breathe like we do and don't use blood to transport oxygen. They take in oxygen and expel carbon dioxide through holes in their bodies called spiracles. These holes connect to branching and interconnecting tubes, called tracheae, Kaiser explained.

Whereas humans have one trachea, insects have a whole tracheal system that transports oxygen to all areas of their bodies and removes carbon dioxide. As the insect grows, tracheal tubes get longer to reach central tissue, and get wider or more numerous to meet the additional oxygen demands of a larger body.

Apparently one of the things limiting the size of insects is that the legs have these tracheae passing through them from the body, make the insect bigger and there isn't room for the tracheae to take oxygen to the legs through the joints. 

So for giant insects you need them to evolve both lungs and transferring oxygen through the blood stream (assuming they have a bloodstream, I don't know, if not they would have to evolve that or an equivalent too). 

[marstone]

yes, the limit seems to be how long the tubes can be to carry anough oxygen into the center of the insect.  It gets to a point that the tubes can not be wide anough to carry the level of oxygen needed.

[Bonk]

Yes, that is exactly what I was referring to from the start. Though not expressed well.

That coconut crab lives on the edge...

[Nemesis]

But it is more than just lungs (which could evolve from the tracheae) but a circulatory system to carry the oxygen.  I don't know much about insect anatomy so I don't know what they have that might be adapted (they must have something to carry nutrients around).  A larger insect could evolve tracheae in its legs bypassing the joint issue and at least allowing larger ones. 

None of this gets around the problems of the exoskeleton.

[Bonk]

There was a higher percentage of atmospheric oxygen so the giant insects were able to get by on a less efficient respiratory system.

Check it out:

http://gsa.confex.com/gsa/2010AM/finalprogram/abstract_181665.htm

I understand they produced dragonflies with a 70cm wingspan!  (no luck with the cockroaches oddly though - perhaps not so odd, they are already a near perfect machine)

... not sure if the image attached to the story is genuine ...