Mad as a Marine Biologist

astronomy-to-zoology:

Tethys fimbria

….is a species of nudibranch found throughout the Mediterranean sea and eastern Atlantic. T.fimbria is a hunter and combs the ocean floor for small crustaceans, scooping them up in its large hood. Although they are often found in the sand, these nudibranchs are also accomplished swimmers  and can often be seen swimming in the water column.

Phylogeny

Animalia-Mollusca-Gastropoda-Dendronotida-Tritonioidea-Tethydidae-Tethys-fimbria

Image Source(s)

High-res rhamphotheca: ‘Giant Squid’ Are Indeed All One Species by Stephanie Pappas Though they roam the deep sea around the globe, enigmatic giant squid are all part of the same species, new research finds. The new study reveals that the genetic diversity of giant squid (Architeuthis) is remarkably low — far lower than that of other marine species examined, said study researcher Tom Gilbert of the University of Copenhagen. The findings suggest that the squid intermingle and mate across the globe. “The results are extremely surprising,” Gilbert told LiveScience. Giant squid are mysterious creatures. They dwell in the deep ocean, making them difficult to observe in their natural habitats. In fact, no one had observed a live giant squid in the wild until 2004. The first video of a live giant squid wasn’t released until this year. The animals appear to grow as long as 60 ft (18 m) and are carnivores that prey on fish and other squid… (read more: Live Science)                     (photo: Mark Norman)

rhamphotheca:

‘Giant Squid’ Are Indeed All One Species

by Stephanie Pappas

Though they roam the deep sea around the globe, enigmatic giant squid are all part of the same species, new research finds.

The new study reveals that the genetic diversity of giant squid (Architeuthis) is remarkably low — far lower than that of other marine species examined, said study researcher Tom Gilbert of the University of Copenhagen. The findings suggest that the squid intermingle and mate across the globe.

“The results are extremely surprising,” Gilbert told LiveScience.

Giant squid are mysterious creatures. They dwell in the deep ocean, making them difficult to observe in their natural habitats. In fact, no one had observed a live giant squid in the wild until 2004. The first video of a live giant squid wasn’t released until this year. The animals appear to grow as long as 60 ft (18 m) and are carnivores that prey on fish and other squid…

(read more: Live Science)                     (photo: Mark Norman)

High-res rhamphotheca: Limacina helicina is a free-swimming planktonic snail. These snails, known as pteropods, form a calcium carbonate shell and are an important food source in many marine food webs. As levels of dissolved carbon dioxide in seawater rise, skeletal growth rates of pteropods and other calcium-secreting organisms will be reduced due to the effects of dissolved carbon dioxide on ocean acidity. Learn more about ocean acidification: http://oceanexplorer.noaa.gov/facts/acidification.html. (via: NOAA Office of Ocean Exploration and Research)

rhamphotheca:

Limacina helicina is a free-swimming planktonic snail.

These snails, known as pteropods, form a calcium carbonate shell and are an important food source in many marine food webs. As levels of dissolved carbon dioxide in seawater rise, skeletal growth rates of pteropods and other calcium-secreting organisms will be reduced due to the effects of dissolved carbon dioxide on ocean acidity.

Learn more about ocean acidification: http://oceanexplorer.noaa.gov/facts/acidification.html.

(via: NOAA Office of Ocean Exploration and Research)

rhamphotheca: A cool new way climate change is killing bivalves By Susie Cagle We already know that carbon-dioxide-filled, acidic ocean water is no-good, very-bad news for mussels and other underwater shelled creatures, causing their shells to dissolve. But, as these things so often go, it turns out that climate change is even worse for bivalves than we thought: It’s unleashing an awkward kind of anti-puberty on them. They’re growing smaller and weaker, and now we find out that they’re basically losing their hair. New research published in the journal Nature shows that mussels’ proteinaceuous byssal threads — the little stringy bits that allow them to stick their bodies on stuff — are particularly susceptible to ocean acidification. The researchers found mussels’ little stringy bits were 40 percent weaker when exposed to elevated CO2 levels, even when their shell strength and tissue growth weren’t affected… (read more: Grist.org)                       (photo: Sapphire/Flutterby)

rhamphotheca:

A cool new way climate change is killing bivalves

By Susie Cagle

We already know that carbon-dioxide-filled, acidic ocean water is no-good, very-bad news for mussels and other underwater shelled creatures, causing their shells to dissolve. But, as these things so often go, it turns out that climate change is even worse for bivalves than we thought: It’s unleashing an awkward kind of anti-puberty on them. They’re growing smaller and weaker, and now we find out that they’re basically losing their hair.

New research published in the journal Nature shows that mussels’ proteinaceuous byssal threads — the little stringy bits that allow them to stick their bodies on stuff — are particularly susceptible to ocean acidification. The researchers found mussels’ little stringy bits were 40 percent weaker when exposed to elevated CO2 levels, even when their shell strength and tissue growth weren’t affected…

(read more: Grist.org)                       (photo: Sapphire/Flutterby)

High-res The Disposable Penises of a Nudibranch.  Little did I know, when I shot this critter, that it had a kinky talent of regeneration.  I say ‘it’, because nudibranchs are simultaneous hermaphrodites. During mating, the pair will impregnate each other. With the penis location on the right side, when the nudibranchs line up, they can inseminate themselves at the same time. The act takes anywhere from a few seconds, to a few minutes.   Post-coital observations (for Science) showed that as the nudibranches pushed away from each other, they ‘shed’ their penises.  In less than 24 hours, however, the nudibranchs had regenerated their penises and were able to mate again.  Apparently the reason for this being that a large amount of the penis is stored coiled up in a spiral inside their bodies, used to replace the missing part.  So what’s the advantage?  The researchers say that in the first act of copulation the penis may be used to remove any sperm left by any competitors that its partner has mated with. With the first penis and the rival sperm then abandoned, the second penis can be used to inject the sea slug with another dose of its own sperm, ensuring that their genes are the ones that are passed on. Via: BBC Photo: Samantha Craven Journal Article: http://rsbl.royalsocietypublishing.org/content/9/2/20121150

The Disposable Penises of a Nudibranch. 

Little did I know, when I shot this critter, that it had a kinky talent of regeneration. 

I say ‘it’, because nudibranchs are simultaneous hermaphrodites. During mating, the pair will impregnate each other. With the penis location on the right side, when the nudibranchs line up, they can inseminate themselves at the same time. The act takes anywhere from a few seconds, to a few minutes.  

image

Post-coital observations (for Science) showed that as the nudibranches pushed away from each other, they ‘shed’ their penises. 

In less than 24 hours, however, the nudibranchs had regenerated their penises and were able to mate again. 

Apparently the reason for this being that a large amount of the penis is stored coiled up in a spiral inside their bodies, used to replace the missing part. 

So what’s the advantage? 

The researchers say that in the first act of copulation the penis may be used to remove any sperm left by any competitors that its partner has mated with.

With the first penis and the rival sperm then abandoned, the second penis can be used to inject the sea slug with another dose of its own sperm, ensuring that their genes are the ones that are passed on.

Via: BBC

Photo: Samantha Craven

Journal Article: http://rsbl.royalsocietypublishing.org/content/9/2/20121150

  • BBC