Posts Tagged 'Spider Crab'

Molting spider crab

All arthropods need to molt. Here is a time lapse video of how a spider crab does it.

When a crab is ready to molt it rapidly takes up water, causing pressure to build in its body cavities. The rigid outer exoskeleton breaks open and the crab is able to push itself out from inside its molt. The new exoskeleton is softer, so it is undamaged by the increase in body volume, but it will eventually harden over time. Recently molted, soft-shell blue crabs are commonly steamed and eaten whole in my neck of the woods.

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Arthropod Roundup: Crabzilla, altruistic ants, and neuronal recordings from Drosophila in flight.

Quick notes about recent Arthropod news and research:

  • The National Sealife Centre in Birmingham, England is hosting a special guest, on loan from Japan. Meet ‘Crabzilla’, a not-quite full grown Japanese spider crab, Macrocheira kaempferi. Crabzilla has an impressive leg-span of about 10 ft, but members of this species can reach over 13 ft. By length, they are the largest know arthropods on the planet. You can read more about Crabzilla’s visit to the UK at the Daily Mail.
  • New research on the ant species, Temnothorax unifasciatus, found compelling evidence of altruistic behavior. Altruism is commonly observed in social insects, as single individuals often sacrifice their energies or lives for the good of the colonial super-organism. In the present study, the researchers showed that ants infected with a deadly and contagious fungus would often leave the colony and die in seclusion. This prevents transmission of the disease to other members of the closely interacting colony. Read more at the BBC.
  • Finally, researchers have developed new techniques for recording electrical signals from fruit fly neurons while the animals are in tethered flight. Fruit flies, Drosophila melanogaster are the go-to arthropod model organisms, and a plethora of molecular and physiological tools are available for studying any aspect of their biology. This new neuronal recording technique was applied to look at the activity of visual pathways in the brain during flight. The researchers found that the stimulus response time of the Drosophila visual system nearly doubles when the animal is in flight. This allows the flies to change direction rapidly mid-flight in order to avoid obstacles. This work was published in Nature Neuroscience. Read more at Science Daily.

    A tethered fruit fly in flight with a pink electrode in its brain. Photo by Gaby Maimon and Michael Dickinson.


I have moved.
Arthropoda can now be found here.

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

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