Archive for the 'Uncategorized' Category

Do scarab beetles get to join an exclusive visual sensory club?

Animal visual systems are evolutionarily tuned to exploit environmental light towards the purposes of spatial perception, navigation, and intraspecific communication. We predominately experience visual information based on variations in the intensity and the wavelengths of incoming light; perceived as brightness and colors. Other animals however, especially the arthropods, also rely on an additional visual modality with which to perceive their world. They are capable of detecting and discriminating different polarizations of light waves.

I’ve previously discussed how most arthropods detect linearly polarized light (LPL), and last week I summarized the research making mantis shrimp the first animal known to be capable of detecting and discriminating an additional flavor of polarized light, circularly polarized light (CPL). Now, new research has brought a challenger, a jewel scarab beetle (Chrysina gloriosa), into contention for the exclusive CPL sensitivity club. Lets find out how strong the beetle’s case is, and weather the mantis shrimp is going to have to share (begrudgingly, I’m sure) the spotlight.

Read the rest of this post at Arthropoda’s new home, on the Southern Fried Science Network.


Arthropod Roundup: Trilobites (both fossilized and stuffed), velvet worms, animated stomatopods, and deviant water striders

See this week’s roundup at Arthropoda’s new home on the Southern Fried Science Network.

A not-so-well camouflaged ambush bug

See the photo at Arthropoda’s new home on the Southern Fried Science Network.

How mantis shrimp see circularly polarized light

Mantis shrimp have long been regarded as visual super-stars. They can have up to 16 distinct photoreceptor types that are maximally sensitive to at least 12 different wavelengths (colors) of light; from deep in the ultraviolet, across our visual range, and into the infrared. In addition, they are strongly sensitive to linearly polarized light (LPL) and are able to discriminate the angle at which these waves of light are oscillating as they travel through space. This visual modality, though hugely foreign to us, is actually well perceived by cephalopods, some chordates, and almost universally amongst the arthropods. Mantis shrimp however, seemingly never content to be matched, have taken polarization sensitivity a step beyond any other animal. They have evolved an ingenious means of detecting and discriminating circularly polarized light (CPL)…

Read more at Arthropoda’s new home, on the Southern Fried Science Network.

Trash-covered decorator crab

Trash-covered decorator crab, originally uploaded by Michael Bok.

This crab was found living in the outflow sump system for the research station salt water aquaria system. He has covered himself with plastic, netting and other trash that ends up in the collection basin before the water is sent back out to the sea. The yellow areas on the crab are sponges that the crab actually farms on its body. They provide the dual benefit of camouflage and a portable snack.

Approaching Lizard Island from the air

I snapped this shot as our aircraft began circling in for a landing on the airstrip in the middle of Lizard Island (the island in the background). Palfrey Island is in the foreground, with the protected lagoon in the middle. The research station is barely visible along the leftmost beach on Lizard Island.

Carnival of the Blue #36 is up

The 36th edition of Carnival of the Blue is up at Observations of a Nerd. Go check it out for more salty science than you can shake a bamboo shark at! Next month’s Carnival of the Blue will be at Blogfish. Submit articles via this automatic submission form.

Circus of the Spineless #50

Welcome to the 50th entry in the Circus of the Spineless carnival series. This was the first carnival I ever participated in, and now I’m thrilled and grateful to be hosting CotS as my (relatively) new blog’s very first carnival.

I’ve loosely organized this carnival according to taxonomy and order of submission. Let’s dive right on in to the wonderful world of the invertebrata, beginning with some squishies.

Phylum: Annelida
Class: Clitellata

GrrlScientist, from Living the Scientific Life, starts us off with a moderately gag-worthy post about a nose-dwelling leech, Tyrannobdella rex. This is potentially the most terrifying T. rex I have ever heard of.

Phylum: Mollusca
Class: Gastropoda

Dave Ingram, of Dave Ingram’s Natural History Blog, shares photos and musings about a herd of Grovesnails (Cepaea nemoralis) in his post, Glorious Grovesnails.

Jill Wussow, who writes the improbably named blog, Count your chicken! We’re taking over!, also brings glorious photos of some slippery snails, Redwood Sidebands (Monadenia fidelis).

Phylum: Arthropoda
Subphylum: Hexapoda
Order: Diptera

I’ll kick off the large batch of arthropod submissions with probably the biggest news in the inverte-blogosphere this past month:

This is the end
Dipteran friend
This is the end
My winged friend, the end
Of our taxonomic plan, the end
Of paraphyly that stands, the end
No safety or surprise, the end
I’ll never look into your ommatidia…again

David Winter, at The Avatism, brings us two posts about the taxonomic cataclysm brewing over the Drosophila genus. First, he describes the scientific importance of this Nobel Prize winning insect, and then the fallout surrounding its likely re-naming.

Joan Knapp, at Anybody Seen My Focus?, spotted a truly bizarre fly visiting a flower he was photographing. He managed to snap a few shots and identify this flying fuzzball as a bee fly, Sparnopolius confuses

Order: Hymenoptera

Ted MacRae, of Beetles in the Bush, posted an ant identification Pismire Puzzle. This myrmecine mystery set off an entomologically-epic commentary thread. (I think this entry just fried my alliteration cortex)

The Geek in Question, at Fall To Climb, brings us this post about a mutualistic relationship between ants and aphids. For once the hymenopterans aren’t picking on the helpless aphids.

Roberta Gibson, at Wild About Ants, describes some gall-forming wasps that apparently trick aphid gall-tending ants into protecting their homes without reward. Wasps are possibly the true jerks of hymenoptera.

Zen Faulkes, at NeuroDojo, lends support to my ‘wasps are jerks’ hypothesis with an article about jewel wasps (Ampulex compressa) that commit atrocities of mind control against cockroaches.

Order: Hemiptera

Matthew, at Backyard and Beyond, brings us more gall-forming goodness in his post about aphid and wasp galls found in Brooklyn, of all places. Exciting nature can be lurking anywhere!

Order: Lepidoptera

Chris Grinter, at The Skeptical Moth, goes moth tasting in the Napa Valley and photographically samples some intoxicating vintages of Adelidae fairy moths.

Order: Orthoptera

Joy Kidd, at The Little House in the Not-So-Big Woods, relates her hunt for an elusive Northern Green-Striped grasshopper that seemingly possessed the ability to will itself invisible amongst the leaf-litter.

Zen Faulkes, at NeuroDojo, gives us a second submission about big love among some very big wetas (Deinacrida rugosa). Bonus (possibly?): Fleetwood Mac.

Order: Coleoptera

Fred First, at Fragments From Floyd, inadvertently risks his finger to give us a look at an oil beetle (Meloidae). Also know as blister beetles, they excrete the caustic compound, cantharidin.

Subphylum: Chelicerata
Class: Arachnida

Ed Young, at Not Exactly Rocket Science, discusses the weird mating dynamics of wasp spiders (Argiope bruennichi) and finds males are less likely to be eaten after having sex with their sisters.

Subphylum: Myriapoda
Class: Diplopoda

Dave Ingram, of Dave Ingram’s Natural History Blog, came across a an almond-smelling millipede (Harpaphe haydeniana). It turns out that the smell is cyanide, a defense mechanism for the many-legged forager.

Adrian Thysse, at The Bug Whisperer, got a fancy new macro flash and tried it out on a millipede (genus Cylindroiulus). The little Diplopod proved a willing subject and even yielded a bonus arthropod, tiny mite parasites, attached to its legs.

Subphylum: Crustacea
Order: Decapoda

Kevin Zelnio, at Deep Sea News, has a post about the bizarre visual system of hydrothermal vent shrimp. Their retina has moved to their carapace and may be used to sense blackbody radiation from the vents.

That does it for this month. Thanks for reading, I hope I did the half-centennial of Circus of the Spineless justice.

Next month’s carnival will be at Deep Sea News, so start sending those fine folks your submissions.

I want my own enormous robotic ant

Unleash the awesome!

A robotic engineer has developed a beautifully designed hexapod robot based on the biomechanics of ants. He calls his remote controlled creation A-pod, and cites the photography of Alexander Wild (of Myrmecos) as an influence on his design.

A-pod is capable of a wide range of motions and body contortions. In addition to walking around, A-pod can grasp and carry objects in its metallic mandibles. The motions are incredibly fluid and I can’t imagine the amount of work that had to go into programming the synchronous movements of all six legs. You can watch videos of A-pod in action here and here, and learn more about the construction of the robo-beastie here.

At this point, A-pod just needs to be programmed to find Sarah Connor, and then it can assist in the inevitable robot uprising.

Arthropod Roundup: Amphipods under the ice, high octane isopods, and the pea aphid genome

Quick blurbs about arthropod research and news:

  • NASA climate researchers have discovered animal life deep below the Pine Island Glacier Ice Shelf in Antarctica. The researchers drilled a hole six-hundred feet deep and eight inches wide into the glacial ice sheet about twelve miles from the open ocean. When they lowered a camera below the ice sheet, the scientists were surprised to see a Lyssianasid amphipod crustacean swim up and park on the cable. The researchers were only expecting to find microbial life under the ice sheet this far in from the open ocean. It is unknown what the primary energy source for animals living here could be. The presence of a three-inch amphipod, however, suggests a much more elaborate and dynamic ecosystem than hypothesized in this poorly understood habitat. (DSN has a video of the amphipod)
  • Limnoriid isopods, commonly called gribble worms for some reason (they neither are, nor resemble worms), have a ravenous appetite for wood. This is not unusual among arthropods; many diverse groups including termites, millipedes, and squat lobsters are capable of digesting woody plant matter. However, all these creatures process the wood with the aid of gut-dwelling symbiotic bacteria. A new study finds that the Limnoriid isopod, Limnoria quadripunctata is special in that it doesn’t rely on bacteria-produced catalysts to break down wood, but rather has the necessary glycosyl hydrolase enzymes incorporated into its genome. These enzymes are evolutionarily related to similar proteins found in arthropods, but their derived function for wood digestion in Limnoriid isopods is completely novel. The researchers, or their over-excitable university PR department, think the study of these enzymes could aid in bio fuel synthesis.
  • The gemone of the pea aphid, Acyrthosiphon pisum, has been sequenced. This is the first Hemipteran (true bug) genome and will provide clues about the evolutionary history of certain hexapod groups. This new genome could also help agriculturalists develop new techniques to control aphid pests and the spread of aphid-borne plant viruses. Researchers are also interested in the pea aphid’s, apparently, scaled down immune response system and their ability to easily switch specialization from one plant species to another.

I have moved.
Arthropoda can now be found here.

Michael Bok is a graduate student studying the visual system of mantis shrimp.

Flickr Photos