Zombie Grasshoppers!

I was cleaning up my room last night, and this Orthopteran leg was beneath my desk. Aka, the leg of the same dead grasshopper we used in lab 3 weeks ago and that I placed ever so delicately outside of my friend's room when I was angry at her.

Can someone tell me how it could have happened that, when I disposed of the Orthopteran, its limbs--supposedly dead--managed to crawl their way out of the garbage and into my living space to haunt me for weeks? Remember that this was not the first time I found more Orthopteran limbs floating about. If you recall, I posted about a week ago about a tarsus I had found in my shoe. And, now this! A full leg! Am I dealing with a zombie Orthopteran?!?!??

Speaking of Zombie Orthopterans, there's a grasshopper parasite that lives inside grasshoppers and pumps a cocktail of chemicals through the hemolymph that drives the host to commit suicide by leaping into water. These hairworms trigger the grasshopper's leap of death by meddling with the central nervous system. This relationship was only discovered 7 years ago when a team of French biologists was monitoring grasshoppers that became trapped in a swimming pool on the border of a forest near Avene les Bains in southern France. Hundreds of grasshoppers arrived at the pool most summer night at the behest of the parasites.

Here's a video of the grasshopper suicide, accompanied by an "entretien" (interview) with some Frenchies who discovered this relationship. If you're really interested, I could translate it, but I'm kind of in a coffee shop right now and I lost my pair of headphones. :(

Image source: http://www.nytimes.com/2005/09/06/science/06hopp.html

If you watch the video, you see that the grasshopper sort of has a small wiggling tail before it takes the plunge, and then when it does, the tail gets longer and longer until a full hairworm frees itself from the posteriormost end of the grasshopper, leaving the grasshopper dead and the hairworm free to swim around in the freshwater. 

The French research team looked more into the nature of this bizarre parasitism, and found that the hairworms secrete proteins that influence the grasshopper's CNS.This biochemical tampering appears to drive the grasshopper to water just when the hairworm is ready to reproduce. This is convenient for the hairworm, which spends most of its life eating away the innards of the grasshopper it infects, and then has the grasshopper transport it to freshwater when it is time to reproduce. 

Biron et al. 2005 reports a clear linkage between the Orthopteran's frenzied water-seeking behavior and differential expression of the Orthopteran's CNS and of the hairworm's proteomes. Their proteomic analysis also demonstrated that certain protein families are expressed at key periods during the hairworm's life cycle and the manipulative process.

Though these proteins are produced by the hairworm, they seem to resemble insect-type proteins from the Wnt protein family, which the French biologists suspect were developed mimetically. The Wnt proteins synthesized in the parasite are homologous to, and play an important role in, in the development of CNS (Biron et al. 2005).

The biggest currently-standing question baffling scientists is how these aquatic creatures manage to parasitize terrestrial species. The guy from the interview, Frédéric Thomas, suspects that the minuscule aquatic larvae first infect aquatic insects, like mosquitoes, and then hide as cysts in their tissue. Then, when the adult mosquito flies away and dies, an Orthopteran may consume its dead body, unknowingly consuming the hairworm larvae. The hairworm will then "develop, eating absolutely everything not essential to keep its host alive," said Dr. Thomas. By the time the Orthopteran goes for its final swim, it is reduced to nothing but exoskeleton. 

I can't wait for these zombie-making hairworms to make it on some sci-fi thriller. I'll be at the midnight premiere when it happens.

Also, my final conclusion is not that this is a zombie grasshopper parasitized by a hairworm. I think I'm just terrible at cleaning. Hopefully this will be the last report of unwelcome grasshopper parts in my living space.

References

Biron et al. 2005. Behavioural manipulation in a grasshopper harbouring hairworm: a proteomic approach. Proceedings of the Royal Society. 272(1577): 2117–2126. 

"Suicide Grashoppers Parasitized By Parasite Worms." 1 September 2005. http://news.nationalgeographic.com/news/2005/09/0901_050901_wormparasite_2.html 

Wade, Nicholas. "Parasitic Hairworm Charms Grasshopper Into Taking It For a Swim." New York Times. 6 September 2005. http://www.nytimes.com/2005/09/06/science/06hopp.html

A Very Stable Stabilimentum

My favorite find this summer was a veritable crowd of Argiope in the meadow behind my house.

I have spent countless hours in these fields, but had never noticed the Common Garden Spider, Argiope aurantia. Before I ascertained its harmless identity, I had a few moments of cold terror as I began spotting up their webs all around; at least 20!

This distinct fellow is on page 68 of our lab book Spiders and Their Kin, along with some of its genera.

This particular post was prompted by Thursday's lesson, particularly the bit about stabilimenta, which A. aurantia proudly displays. As we heard in lecture, the functional hypotheses for these lovely decorations are (1) predator defense and (2) prey attraction. 

Stabilimentum visible vertically aligned with A. aurantia's body.

(personal photo)

In my cursory research, results indeed seem to be inconclusive. Some studies note that when starved, stabilimentum production seemed to decrease in Argiope species (Seah and Li, 2002 and Blackledge, 1998). They thus argue it an unlikely prey attraction technique, since it decreases when spiders are presumably seeking bugs--despite low energy output.  Tso 1998 disagrees, as their study finds that the presence of stabilimenta in webs of Cyclosa conica increased prey capture more than any other factor (web diameter, etc). It remains to be seen if there is conclusive variation by species or habitat, or perhaps a continuum of explanations. 

Where we can all agree, I think, is the artistry of the endless variations:

(source: Seah and Li, 2002)

As a side note, I also have an Argiope mystery on my hands.

In my enthusiasm for those in my backyard, I started to see A. aurantia & kin everywhere! A pondside hosted what I thought were Argiope bruennichi, cleverly suspended between cattails. 

I didn't get a shot of the ones I saw, so here's a stock photo...

(Source: Wikimedia Commons)

Sadly, page 68 of Spiders and Their Kin thinks A. bruennichi are only in Europe, and the widely renowned Wikipedia seems to agree, though I'd've bet my collembola collection I was right. Does anyone have light to cast on what I may have seen? Have they hopped the pond?  

Spider in Action: McClellan Hall

I was making my way back to my room after Safety Dance when I chanced upon an epic struggle of life and death..... a small araneid was feasting on a dipteran easily twice its size. Actually, I think it was no longer a struggle by the time I got there. It seems that the spider was already ingesting the liquified contents of the dipteran. The web seemed more fluffy than orb-like....I will post again when I have identified it properly. Also, note the mosquito that had also been caught (probably eaten already, just leaving the exoskeleton).
This spider is doing well. I will go back for updates sometime this week

Poor pinning, and some really cool bugs

I made my first insect collection in fifth grade, and have been keeping it in my closet at home. I was considering having my mom mail some of it to me, until I realized that everything was pretty badly pinned, and I didn't really have that much interesting stuff anyways (the shiny green beetles are pretty cool, but I forgot to label them...). Anyways, my mom graciously took pictures of my bugs, so here they are.

I originally had all of these pinned to a piece of cardboard in a plastic pencil box, until my granddad gave me this snazzy box.

Hopefully my pinning skills have improved since fifth grade...

My mom also sent me some pictures of my granddaddy's collection, most of which has ended up in a museum at this point. My granddad wasn't an entomologist, but he was a chemistry professor who loved collecting insects (as well as minerals and stamps and African art. And cacti.). He taught at UCSB but was able to get crazy-awesome teaching gigs in other countries, and subsequently traveled all around the world when my mom was young. They lived in Malaysia for a year when my mom was eleven, and in Liberia for a year when she was sixteen. My mom spent a lot of her childhood holding a butterfly net and running around the jungle with my granddad. I guess some are luckier than others...

So here are some pictures of just a tiny portion of his collection. I tried to add captions, but I couldn't come up with unique things to say for each picture. All I could think was These. Are. So. Cool.

A pet?

So, after today's spider lecture, I was inspired to gain some intimacy with spiders, and have resolved to get a tarantula (Theraphosidae) for myself to keep in my room (don't tell my Dean).

I haven't done much research about choosing and caring for tarantulas, but I have found three different Connecticut Craigslist posts for tarantulas. Help me determine which is the least sketchy, and which one I should pursue?

1: Rose Hair Tarantula (pretty, but overpriced, I think)
2: P. Murinus (it's orange!!!)
3: Avic Versi (no picture, but cool species)

If it's a boy, I will name it Igor. If it's a female, I will name it Inga.

Thoughts? Where else should I look besides... erm... Craigslist? And what will I need to take care of it?

CSI: New Haven (Catching Some Insects: New Haven)

Our trip to Sleeping Giant State Park last weekend netted a good haul of insects. The trip started off with an unfortunately all-too-familiar sight: a dead body laying on the side of the road. I was mortified by the zeal and bloodlust of the students (and Val) as they ran towards the corpse.

Alien Ninjas and Food Chain Reversal

Here is a BAMF of a bug.

Giant Devil's Flower Mantis (aka alien ninja)

And here are several things about this bug that make me extremely happy:

• Its Latin name is Idolomantis diabolica.
• It mimics flowers, so that sometimes prey flies directly into it.
• It is the largest--and rarest--mantis.
• It can be found in eastern Africa (winter break trip?).
• Each instar is a different color. 1st instar is black, some of the middle instars are brown and leaf-like, and the last instar is brightly colored like the alien ninja in the picture above. 
• On its Wikipedia page, all of the colors are hyperlinked.

Speaking of badass mantises, one of our lecture powerpoints had this picture in it...

...which is vaguely disturbing slash really cool.

So I decided to do a little bit of research and find out whether the bird-eating mantis was actually a thing.

First, I found this wonderful affirmation of the intelligence and benevolence of the human race.

And then I found this.

So mantises do eat birds. And it turns out they eat a lot of other things, too, including snakes, rodents, and each other. And apparently humans, as long as they're small. Mantis mouthparts are well-suited to this rampant carnivory, seeing as they consist of hugely overgrown mandibles.

According to a study about size-based prey recognition in mantises, volume (as opposed to width, length, shape, or area) is the most important consideration for hungry mantises. Apparently mantises use the volume of their prey as an indicator of its energy content. In the study, the volume that elicited a "watch response" (basically the precursor to an attack, where the mantis scopes out its quarry) with the highest frequency was 112.2 cubic millimeters, about the size of a cube with half-centimeter sides. That's pretty small, especially considering that they used 7 cm long mantises for the study. So I guess that mantises usually prefer smaller fare, and the whole bird-and-reptile-and-mammal-eating thing is a little less common.