SICB Lessons: Mantis shrimp are AWESOME

this Odontodactylus scyllarus is just oozing awesomeness

OK, OK, this isn’t really something I needed to learn at a conference, but this fact is reinforced every time I go to SICB. That’s because I get to see presentations about these cool stomatopods from Sheila Patek and her lab. They look at the muscle physiology and mechanics of mantis shrimp raptorial appendages. You can read the 2010 abstract here and the 2011 abstract here. The main take-away message is that mantis shrimp are super fast and wicked strong!

[This is a long video, but really interesting if you have the time.]

I also learned that, within 8 genera, there are monogamous mantis shrimp (at least for one breeding season) from Molly Wright with UC Berkeley. So that means that we can stop worshipping those pesky penguins as our models for (eternal) love!

I sketched that guy, so sorry if it's not entirely accurate

(Feel free to use this card for your loved ones:

1. Download it and print it out on white card stock, trimming any edges

2. Fold on the grey dashed line

3. Write something meaningful inside like, "... at least for this year" or "I smashed some snails just for you! Love, Me" (that last one would be great if you have escargot on hand))

I linked up to the XLV Carnival of the Blue:

SICB Lessons: You can’t trust a fiddler crab

can you believe this guy?

Fiddler crabs lie! Well, that’s not exactly true. But male two-toned fiddler crabs Uca vomeris can be misleading when it comes to their displays of strength. Males will wave their large chela to show off their guns and attract mates, but some males’ large claws have been broken off and regenerated. A regenerated claw, while being the same length, is often skinnier and weaker, as seen in U. pugilator from South Carolina:

a normal U. pugilator claw on the left compared to a regenerated claw on the right:

the regenerated claw is skinnier and missing the teeth and tubercles

(v = manus length, iii = dactyl length, iv = propodus length)

Candice Bywater of the University of Queensland monitored behavior of male U. vomeris and measured their claw strength and metabolic rates to compare regenerated vs. original claw action and strength. While regenerated claws were, in fact, weaker, that didn’t stop the males from putting their claws in the air like they just don’t care. Males with regenerated claws were basically saying, "Hey ladies, I can protect you from that other dude", even if they can't. Bywater calls this type of deceit ‘unreliable signaling’ and presented her work at the 2011 SICB Symposium.

SQUEEEEEEZE!
Uca vomeris in Candice's lab

She has also seen unreliable signaling in Australian freshwater crayfish Cherax dispar males. Dominance is determined by claw size for both males and females, but while females have to back up their size with strength, male claw strength is not as important for determining social standing. Two males of similar claw size may not have similar claw strength, therefore, when they display their claws before a battle, they may be dishonest about their true strength.

fight! fight! fight!

For discussion’s sake, the congener C. destructor showed male dominance to be dependent on both size and strength while females only needed bigger, not stronger, chelae. Go figure.

I wonder what this one is trying to signal to us

What's that you say?

Bywater, C., M. J. Angilletta, and R. S. Wilson. 2008. Weapon size is a reliable predictor of weapon strength and social dominance in females of the slender crayfish. Functional Ecology 22: 311-316.

McLain, D. K., L.D. McBrayer, A.E. Pratt, and S. Moore. 2010. Performance capacity of fiddler crab males with regenerated versus original claws and success by claw type in territorial contests. Ethology Ecology & Evolution 22: 37–49.

Yo, that’s so SIC, B!

I just got back from Salt Lake City, host of the 2011 Society for Integrative and Comparative Biology (SICB) meeting. I love this meeting because I can learn a lot about crabs and reproductive physiology, but I can also learn about snakes that glide, armadillo development, and roboclams! (Yes, roboclams.)

the roboclam next to its inspiration, a razor clam

I also bumped into some Southampton College graduates (we’re a rare bunch, since the school closed a year before we graduated) and got to learn about locomotion and feeding in silver-spotted and tidepool sculpins from Emily Kane and FoxG expression in the brachiopod Terebratalia transversa from Carlee Resh.

SC represent!

I can’t wait to share all of the things I learned about crabs from this meeting, like how Florida fighting conchs (Strombus sp.) have evolved thicker lips to hypothetically defend against stone crab (Menippe sp.) predation! (You can read the abstract here.)

So stay crabby and stay tuned!

taking in the Salt Lake City sights:

my crab pin in Temple Square

my pin delighting in the pirate-themed luminary

ARG!

(Psst: check us out in the news: Juneau Empire!)