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Friday, May 30, 2008

Fun with Latin & the Power of Names

One of the basic fundamentals of biology is about nomenclature aka its all about the NAMES of the species!

The scientific names of all organisms are overseen and regulated by an international commission which regulates basic rules of how animals, plants, and other organisms are described and named. For animals this is The International Code of Zoological Nomenclature (or ICZN). For plants, its the International Code of Botanical Nomenclature, etc. Scientific names are in Latin or Greek. Latin was historically the language of scholars and is also conveniently dead, making its use for various scientific and biological endeavors quite convenient.

 Unfortunately, because these words are out of common usage most people have NO frakking idea what you're talking about-whether its at cocktail parties or in a classroom.

Sometimes, scientific names are kind of obscure and require a little knowledge about the history of the species involved, but most times, names are pretty straightforward descriptions of the animals if you translate them from Latin (or Greek) into English...

 So, for example, this beast: the genus Solaster. Sol or solaris is Latin for "sun" and -aster is Latin for star. So the name literally means "sun star" which alludes to its very sun-like or stellate appearance. Equally straightforward is something like this beast: Oreaster reticulatus from the tropical Atlantic. Oreas is from the Greek/Latin for "mountain" and -aster for "star" translates to "Mountain star". The 2nd part of the name is an adjective. Reticulatus literally translates into "net-like" or netted (alluding to the patterns on the surface)..so the complete name Oreaster reticulatus can be read as "Netted Mountain star" Tosia australis? The beautiful biscuit star found in Australia? This one is easy Tosia is actually a Latin word for "Inestimable" and australis simply refers to "south" or "southern". But what about some of these other stranger names? Like this one: Luidia? Turns out, this one is actually named for Edward Lhuyd, a Welsh naturalist from the 17th-18th Century. Lots of guys back then used to give themselves fancy Latin names in the fashion of Carl von Linne' (aka Linneus). His latin name was Luidius. Luidius was known for some interesting discoveries including (but probably not limited to):
  • He apparently was responsible for the first scientific description of what the modern world would call a dinosaur.
  • He also published one of the first major papers on stellate echinoderms in 1703: The Praelectio de Stellis Marinis Oceani Brittanici.

Another starfish named for a naturalist you've probably never heard of? Naroda . This beast was named for the Italian naturalist Giovanni Domenico Nardo from Chioggi, Italy who was part of the starfish crowd back in the 19th century. Its been said for demons and other magical entities that knowing its name gave you power over it. I think that might even be true for animals

Tuesday, May 27, 2008

New Sea Urchin species...on Ebay?????

So, according to two news articles from the U.K: One from the BBC and one from the UK Guardian a new species of the tropical deep-sea urchin Coelopleurus exquisitus from New Caledonia was described by Dr. Simon Coppard from the Natural History Museum in London based, at least, in part on specimens obtained from the online auction house Ebay!

Although the articles I read didn't indicate how much he paid, auctions for these animals apparently start in the $8 to $12 USD range and have been bid up to $138 USD (especially following the discovery that they were a new species).
(from the BBC)
Its been getting quite common for exotic sea urchin species to be put up for sale on ebay and there is now a considerable collector's community/market for sea urchins, including this (among others on ebay and elsewhere):


Echinoids.nl-An elaborate collector's database for sea urchin tests.

An amateur or non-professional community is a fact of life if you work on fossils or on seashells.

These organizations can do a lot of good towards forwarding the study of these fields but have also met with criticism and concern. Much of it based on the creation of a collector's or retail market for fossils or shells or ? which are the bread and butter of paleontologists and malacologists.

How does creating a collector's market for studying sea urchins affect conservation?

How does it affect the study of these organisms?

What is the net input of non-professional collectors to the academic study of sea urchins?

I guess, we'll have to wait and see.


Sunday, May 25, 2008

Memorial Day- Echinoderm Videos!

So..its Memorial Day, a holiday in the United States. When I was in high school and the teacher had an odd day when no learning was possible he or she would just show an educational movie. So, that's what I'm doing here. Enjoy these weird echinoderm videos courtesy of Youtube and NOAA!

Here is a link to video of the deep-sea swimming sea cucumber from the Tropical Atlantic.

And here are some other fun things:

Sand Dollar (Dendraster excentricus) Time Lapse!





Tropical Holothurian Time Lapse feeding


Crinoid Swimming!

Tuesday, May 20, 2008

Japanese Echinoderm Kawaii (Japanese cartoon mascots)

A recent post by my friend Matt Alt at AltJapan describes new Japanese mascots in honor of 2008, the International Year of the Reef.

These mascots are known in Japan as kawaii(for more info on kawaii go check out Matt's book-"Hello, Please"), and in this case are specifically geared at celebrating or publicizing a major event. The SEVEN kawaii are best summarized by Matt himself:
Clockwise from left, you've got Oniide (a super-cute crown-of-thorns starfish, nicknamed the "demon-star" in Japanese for its toxic spines), Shota (the boy with coral for hair), Kacchi, Chu, and Zou (a trio of coral polyps), Taiyo-Kun (the sun), Unibo (a sea urchin), Kanirin (a crab-girl) and Jangurasu (sea grass). The mascots were named in a nationwide competition; a 76-year-old from Fukushima submitted "Shota," while a 7-year-old from Tokyo came up with "Taiyo-Kun," showing the huge popularity of "working characters" (as we call them in Hello, Please) across a wide demographic in Japan.
TWO of these mascots are prominent coral-reef echinoderms. Both of which were taxa included in my recent post on corallivorous echinoderms...specifically Acanthaster planci, the Crown-of Thorns Starfish
Oniide is the very cute cartoon version not to be mistaken for this formidible beast:

and Diadema, the black needle urchin (this is my interpretation-there are quite a few coral reef echinoids that this might represent) as represented by Unibo (think of Uni from your local sushi restaurant)


Regardless of their perceived "threat" or "menace" both of these organisms occupy positions of ecological importance in coral reef systems and so, widespread awareness of not just the reef but its component inhabitant animals remains an important priority.

And hence... cool Japanese mascots!!

Sunday, May 18, 2008

May I introduce...Brittlestar City!!!

(from NIWA 2008)
Wow!
Over the weekend, what can only be described as an enormous echinoderm suspension feeding colony was discovered on Macquarie Ridge by the R/V Tangaroa operated by my good friends at NIWA in Wellington, New Zealand. This involved scientists working in association with the Census of Marine Life.

Video can be seen here.

Looks to be a MASSIVE group of Ophiacantha spp., including Ophiacantha otagoensis and Ophiacantha fidelis
(from NIWA 2008)

And not to be left out..a brisingid suspension feeding starfish. Hard to see which one it is from here...

(from NIWA 2008)

This was not only ophiuroids and asteroids...but also sea urchins, corals, sponges, and seems to be conspicuously dominated by invertebrates...

To quote directly from the CENSEAM Press Release:
Census of Marine Life-affiliated scientists, plumbing the secrets of a vast underwater mountain range south of New Zealand, captured the first images of a novel "Brittlestar City" that colonized against daunting odds the peak of a seamount - an underwater summit taller than the world's tallest building.
Its cramped starfish-like inhabitants, tens of millions living arm tip to arm tip, owe their success to the seamount's shape and to the swirling circumpolar current flowing over and around it at roughly four kilometers per hour. It allows Brittlestar City's underwater denizens to capture passing food simply by raising their arms, and it sweeps away fish and other hovering would-be predators.
This has started to pick among the International News...

Could this be another example of the Paleozoic style ecosystem we discussed in the Antarctic last week?

Thursday, May 15, 2008

21st Century Global Warming threatens Paleozoic style Antarctic Ecosystem

When most people think about Antarctica, they usually think about ice. Glaciers. Penguins. Doomed European explorers in wooden ships. Blah, blah, blah.. All of the typical things we think about because we live on the surface.

What most people don't realize is that the marine systems (i.e., the life BELOW the ice) is MUCH more fascinating. Why? I'll tell you. And then, I'll tell you why its in danger.

First...Antarctica has a Paleozoic style (or more broadly..a retrograde) style ecosystem.
What does this mean?

Essentially, that there is a significant absence of shell or bone crushing (aka durophagous) predators.
Although this can include a diversity of organisms in the general sense, it refers to crabs
(from Flickr)
as well as fish and/or sharks with big jaws and/or the ability to crush bony armor..like this Paleozoic Dunkleosteus
(from Flickr)
These types of predators worked to cull suspension feeding and other soft-bodied invertebrate prey. They would bite off tentacles, arms, etc. and basically not encourage big floating nemertean steaks to swim unescorted through the water.

In the Paleozoic, before these kinds of predators emerged on the scene there were widespread occurrences of these kinds of animals..brachiopods, crinoids, corals, bryozoans, etc.

Flash forward to today.
(from wikipedia)

Antarctica
has a marine bottom fauna that essentially has a rich diversity of ophiuroids, crinoids, giant worms of various kinds, sponges, corals, sea spiders, and everything in between.. But few to no crabs or fish!
(from Pangea.de)
So..that's pretty cool. Its a big playground where invertebrates can rule amongst themselves and run amok!!

Plus, suspension feeders can feed with arms outstretched to their heart's (or whatever) desire!
Soft bodied animals run around all over the place. Invertebrates prey on invertebrates with no big bony predators to harass them.

BUT, a new theat emerges from global warming. Paper for this is here.

With the global change comes a temperature increase and alteration of underwater chemical physiology (and reported in the BBC here).

Sez Dr. Richard Aronson at the Dauphin Island Sea Lab
The frigid water makes it hard for the crabs to efficiently flush magnesium out of their bodies. Too much magnesium acts like a narcotic on a crab.
When it's too cold, the magnesium makes them pass out and die. That's probably why the crabs have been absent for eons. Now, however, in those slightly warmer depths off the continental shelf, it's just warm enough for the crabs to survive there.
As the upper waters continue to warm, nothing will stop the king crabs from moving up onto the continental shelf and feasting. That will "hammer" the old seafloor communities.
(from Flickr)
How will this change the nature of this unique ecosystem?

This is a great example of how biodiversity monitoring, i.e., taxonomy and knowing the composition of the fauna play important global roles in monitoring the impacts of global change. How will the faunal composition shift with the temperature flucutations?

We have seen faunal composition shifts in the past with the Eocene/Oligocene boundary and many other examples...Some move off into more friendly quarters..whereas others pass on into the night..

How will an invasion of crabs, sharks and fish change the integrity and dynamics of this "Paleozoic" style ecosystem?

Monday, May 12, 2008

Fossil Starfish Story: The Deep Sea-Antarctic-Global Warming in Reverse Connection!

(from Littoraria on Flickr)
Believe it or not, when you get under the ice there are more than a few decent places to find fossils in Antarctica (see above).

Work by Dan Blake at the University of Illinois and colleagues have recovered a great many invertebrate fossils from Seymour Island, a small island in the Antarctic Peninsula region.

Seymour Island deposits a great many invertebrates, including mollusks, crinoids, and sea urchins. But there was an incredible diversity of fossil asterozoans, including 6 genera and species of asteroids and one genus/species of ophiuroids.

Specifically, we see how paleontology intersects with the deep-sea, the Antarctic and Climate Change.

To illustrate how this all ties together..let me introduce you to one animal in particular:

The genus Zoroaster (family Zoroasteridae). A genus of starfish with about 20 species that occurs primarily in the deep-sea (~300-5000 meters) throughout the world in the Pacific, Atlantic, and Indian ocean basins. Mah 2007 recently developed a phylogeny and monographed the group. Zoroasterids are interesting because they have only a single marginal plate series, which is a character shared by many Paleozoic forms, but that is only one of the many reasons they are among the most interesting of starfish to study..

Zoroaster sp. from the North Pacific:
and now, here is one from the Eocene La Meseta formation of Seymour Island in Antarctica!! Fragments apparently were not uncommon in the area.
(courtesy of Dan Blake, UIUC)
Another quick comparison of a living Zoroaster sp.
and an Eocene (i.e., fossil) Zoroaster from Seymour Island.

Morphologically, they are VERY close.

Some interesting points:

1. Living Zoroaster live in deep-water habitats. vs. fossil Zoroaster which lived in shallow-water sediments (i.e., the ancient environment can be inferred by geologists to be shallow-water based on distribution of the fossils, and the sedimentary features such as size, composition, sorting and a number of other physical characteristics including the form of the sediment distribution and formation ).

In theory, you could have literally gone wading on Seymour Island during the Eocene and picked up one of these starfish (that today live in 1000 m depths!) in knee-deep water!!!
(from Littoraria on Flickr)

2. Eocene Zoroaster lived in pre-glacial settings. The Eocene Antarctic was much warmer than it was today, resembling the Pacific Northwest in many ways. Temperate rorests extended to the poles. A substantial climate change event took place during the Eocene/Oligocene, which saw the formation of the Antarctic Counter Current and the glaciation of Antarctica.

3. Interestingly, to my knowledge, Zoroaster (and indeed no zoroasterids) have ever been recorded from the Southern Ocean today. (although they are found in adjacent sub-Antarctic waters outside the ACC). But of course, absence of presence is not presence of absence..

Lots of Questions:
  • Did Zoroaster go extinct? or shift into deeper water?
  • Was this part of the recent radiation of Zoroaster in the deep-sea?
  • What about other fossil starfish or invertebrate taxa at Seymour Island?
  • Why did Zoroaster "lose its foothold" in the Antarctic? Climate? Food? Both?
So we see some interesting recent precedents. Starfish give us insights into major and relevant questions simply by being there.....and then not being there.

Thursday, May 8, 2008

Crazy Weird Friday: Brittle Stars from the Antarctic

As part of my ongoing survey of weird Antarctic echinoderms, today we feature among the strangest-the ophiuroids!!

Aside from their very unusual morphology very little about the biology of the critters described below is known. What some of the weird structures do (if anything), what they eat, how they live-all things we know nothing about.

For all those Ophiuroid Taxonomists out there? Check out this recent paper by Martynov & Litvinova (2008) as well as the phylogeny by Rebecca Hunter at Auburn University. Abstract here.

All are members of the Ophiuridae:



1. Here we have: Ophioplinthus gelida (Koehler 1901)
(formerly Ophiurolepis)

What's WEIRD and neat about this one? See all of that shaggy stuff on the bottom specimen? That's a SPONGE (Iophon radiatus) which LIVES ON IT. Here is another picture of it on a living specimen. Apparently, that sponge species lives ONLY on O. gelida!! Not all of them have it..but they usually end up covering the disk, arms and etc.

Nothing published (that I could find anyway) on how the sponge settles..under what conditions the sponge settles, whether it is truly commensal or perhaps parasitic in some way? What is interesting is that Iophon sp. lives on a variety of hosts including crinoids, holothurians, gorgonians, sea urchins, and a variety of mollusks.



Ophiomages looks like huge medeival mace with arms!! It includes one species, O. cristatus and that it occurs in the Antarctic region where it is seldom encountered.


3. And last but not least...Ophiosteira sp.

A weird-looking beast. Have no idea what those knobs are for.
Ophiosteira spp. includes 8 species and occurs widely throughout the Antarctic region but there's very little known about its biology. O. echinulata has been documented as feeding on detritus and dead meat.

Effect of acidification on ophiuroids

A recent new article showing the effect of acidification on amphiurid ophiuroids is nicely summarized

here:
http://sciencenow.sciencemag.org/cgi/content/full/2008/507/3

and by the good Mr. Heupel over at Other 95%..
http://other95.blogspot.com/

professional article is here (Wood et al., 2008)

Ongoing Antarctic stuff tomorrow!

Tuesday, May 6, 2008

Giant Monster Starfish ALERT (aka Labidiaster annulatus) from THE SOUTH POLE!!!

ye olde tale of Antarctick Monstrosity....

One of, if not THE most rewarding experience I had when visiting Antarctica was finally getting to see this animal ALIVE.

When I began studying starfish many years ago, I was captivated by this paper by John H. Dearborn, K.C. Edwards & D.B. Fratt 1991 who very wonderfully described the feeding biology and behavior of Labidiaster annulatus...a large BENTHOPELAGIC predator in the Southern Ocean ecosystem!
yes, you heard that right. A starfish that EATS mobile SWIMMING prey. Not just the odd, errant sick fish..but small, fast moving krill on a regular basis!!

How?
Labidiaster annulatus uses these crazy long arms (note the rings which contribute to the skeletal flexibility) to wrap around, nab or otherwise grab prey in conjunction with these helpful things....
(pedicellariae from Dearborn et al. 1991)
These nightmares from a dental convention are awesome structures are known as PEDICELLARIAE.
Essentially, they are jaw/claw-shaped structures that literally cover the surface of the animal like a big dangerous, shaggy rug covered with bear traps.

When small krill or other prey settle, get too close or otherwise get within striking distance..the starfish GRABS the food with the pedicellariae or its arms and DRAGS the prey via the arms and tube feet down to the mouth, where it is digested immediately by the stomach.

Labidiaster does eat other food..moribund material, etc. as opportunity presents. But gut contents suggest that pelagic prey...amphipods, krill, etc. are its preferred prey. The picture below was taken after having fed a Labidiaster specimen at the Palmer station Marine Lab aquaria.

But even this is only PART of the picture. Other physical aspects contribute to the striking image of this beast:

1. Labidiaster is BIG. With arms outstretched...these animals can reach and possibly surpass a diameter of TWO FEET!

2. They PERCH. That is, they find places to crawl up onto in order to take advantage of water flow...so they sit like kings on sponges, rocks, or what have you and sit above the substratum with their immense arms outstretched like large deadly flowers.

3. Labidiaster is very abundant within its range. Basically, Labidiaster is one of the most numerous starfish to be found in the South Shetland Island/Antarctic Peninsula region (see Manjon-Cabeza et al. 2001)

These Antarctic benthos look like a scene out of some terrifying Lovecraftian-horror story...Large tentacled starfish sitting on their monstrous poriferan thrones ruling over the obsequious but ravenous brittle stars, swimming carnivorous ribbon worms, and who knows what other crazy stuff running amok!! But curiously...NO Fish!! Something I will go into further detail later on...

Monday, May 5, 2008

The Antarctic Echinoderm Experience!

In May 2006 I was on my way to seeing Antarctica for the first time. The anniversary of that trip is coming up, so I thought it would be great to commemorate that experience with a series of articles on Antarctic echinoderms and other related aspects-as well as some of the travel experiences involved.

But a brief summary of why someone like me finds Antarctica so interesting (I will blog in further detail on these topics later):

*The majority of starfish in Antarctica (and there are MANY starfish in Antarctica-not many people realize this) BROOD their young.

*The Antarctic has an unusual Paleozoic-type ecosystem

*MANY asteroids and ophiuroids FEED on MOBILE prey like krill, shrimps, and fish

*Antarctic faunas are often connected with deep-sea faunas

*Glaciers began to cover Antarctica about 35-40 Mya as part of the Eocene/Oligocene climate change event. Are the faunas related?

*There are FOSSILS in Antarctica. What do they say?

A Brief Travelog from May-June 2006
(there's more...and but there's a lot to write about...)

I was onboard ship between May-June (which is austral winter in Antarctica) for about a month-but, along with the crew, was constantly on the go. For those who haven't been on these kinds of cruises, its not unusual to run operations for almost 24 hours.

Our home was the NSF vessel R/V Lawrence M. Gould a noble vessel with a dedicated and devout crew. The Gould took us from Punta Arenas, Chile through the Drake Passage to Palmer Station, out to the far ends of the Antarctic Peninsula and back again...
I had joined a scientific expedition jointly run by Ken Halanych at Auburn University and Rudy Sheltema from Wood's Hole Oceanographic Institution. Their project was aimed at investigating biogeographic relationships across the Antarctic and the Magellanic regions (Chile, the Drake Passage, etc.) as well as the larval connection between those areas.

I was called along as their "starfish expert" to help ID the numerous specimens collected during the course of the cruise.
But there were many experts onboard ship: larval and benthic ecologists, coral biologists, oceanographers, invertebrate zoologists, microbiologists taken from a wide variety of people from different academic station: PhDs, postdocs (like me), grads, and undergrads...a broad diversity.


Specimens were collected from the bottom using a variety of dredge nets....

and larvae/pelagic critters were sampled using a variety of plankton tows and nets..
Collected specimens were sorted, preserved, fixed, photographed, stamped, enveloped, frozen sifted, and prepared for further scientific study...

Antarctica has a HUGE diversity of invertebrates. I think that I must have seen just about every weird representative of major invertebrate groups around. These were photographed from the display tanks in Palmer station...

And when we were done..and returned to Punta Arenas? Well, lets say that as great as food on the LM Gould was..its great to get back to this... Mmmmm..chocolate..