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Articles on this Page
- 10/09/12--23:00: _2012 Cephalopod Awa...
- 10/16/12--23:29: _Fossil Parasites & ...
- 10/22/12--09:53: _Benthic Ctenophore ...
- 10/30/12--19:45: _Five SPOOKY Things ...
- 11/06/12--19:47: _Sea Star/Starfish C...
- 11/07/12--19:02: _Starfish? Cthulhu? ...
- 11/13/12--13:29: _Paris!
- 11/20/12--13:55: _Paris! Sea Urchins ...
- 11/27/12--16:02: _Off-topic: Sea Spid...
- 12/05/12--03:15: _Off-topic: A Panopl...
- 12/11/12--21:43: _Hawaiian Brisingid ...
- 12/19/12--00:18: _Biodiversity Spotli...
- 12/25/12--13:33: _Happy Heterocentrot...
- 12/31/12--14:15: _400th POST! 2012 Co...
- 01/09/13--00:54: _5 Unusual Invertebr...
- 01/15/13--22:54: _A Galaxy Class of G...
- 01/22/13--17:40: _Time Lapse Starfish...
- 01/29/13--22:57: _Echinoderm Tube Fee...
- 02/05/13--23:14: _Brittle Stars Have ...
- 02/12/13--22:21: _Starfish Mystery! 3...
- 10/22/12--09:53: Benthic Ctenophore Video Watch!
- 10/30/12--19:45: Five SPOOKY Things about Echinoderms! Happy Halloween!
- 11/06/12--19:47: Sea Star/Starfish Close Ups!
- 11/07/12--19:02: Starfish? Cthulhu? .....or both?
- 11/13/12--13:29: Paris!
- Describing New Taxa, including genera and species!
- Extracting DNA and "barcoding" populations to study relationships across different areas (ie biogeography)
- Extracting DNA and studying evolutionary relationships among different species
- Discovering parasites in their hosts!
- Studying the full sizes of a species to see how they change. (e.g., think of caterpillars to butterflies to realize how this is important)
- Ecological Modelling
- You find something new in the collections,
- Sequence it for its DNA (or analyze its external appearance), discover it is close to an existing species...
- Compare the specimen to a historical voucher (often called a type) to see if it conforms to the established definition. Is it a new species? A rarely seen species?
- 11/20/12--13:55: Paris! Sea Urchins or Street Urchins?
- 11/27/12--16:02: Off-topic: Sea Spiders (aka Pycnogonids) Galore!
- 12/05/12--03:15: Off-topic: A Panoply of Polychaetes! Photos by Arthur Anker
- 12/11/12--21:43: Hawaiian Brisingid Starfish Munitions Mysteries!
- 12/19/12--00:18: Biodiversity Spotlight on: The NMNH Invertebrate Zoology Department!
- The Collection includes a representative of every recognized animal phylum, including the two most recently recognized-the Loricifera and the Cycliophora!
- You can always check the holdings by going to the online catalog here!
- The dept. has over ONE MILLION cataloged specimens in its database!
- IZ oversees one of, if not the largest collection of Antarctic invertebrates in North America. Here is the USARP page!
- IZ currently hosts 10 active on-staff research zoologists whose interests range from deep-sea cucumbers, freshwater mollusks, midwater polychaete worms, to barcoding and understanding tropical biodiversity.
- Go Check out the IZ Twitter page: @InvertebratesDC
- 12/25/12--13:33: Happy Heterocentrotus Holidays from the Echinoblog!
- 12/31/12--14:15: 400th POST! 2012 Cool Happenings & Top Posts from the Echinoblog!
- 01/22/13--17:40: Time Lapse Starfish Videos!
- 01/29/13--22:57: Echinoderm Tube Feet Don't Suck! They Stick!
- 02/05/13--23:14: Brittle Stars Have TEETH! What do they use them for?
- 02/12/13--22:21: Starfish Mystery! 3 Oceans,2 Hemispheres,but ONE species?!
- the North Pacific-Aleutian Islands/Alaska
- the South Pacific-Chile, Solomon Islands and New Zealand
- the Kerguelen Islands in the South Indian Ocean (sub Antarctic),
- the North Atlantic, the North Pacific-Aleutian Islands
- There was apparently NO gene flow across the Arctic and we couldn't find any records of this species currently present in the Arctic. So, in one sense they took the long way around....
- Modelling studies of the genes showed that the three populations had been diverging with little or no connection (i.e. gene flow) for the past 50 to 75,000 years (roughly the late Pleistocene when).
- That means that this species spread out over the world's oceans QUICKLY (not even a million years!) and not that long ago! That in itself is pretty surprising...
- Could the distribution of these animals (originally spread via swimming marine larvae) be affected by glacial (i.e. ice) cover?
- Although evidence was not concrete-it seems likely that Hippasteria spread out from the Pacific to the Atlantic.
- This was not a case of spread from human transport. We know this because one of the genes we looked at had changed too much to have occurred in a human time frame.
I did this last year and showed some weird artsy pics from a friend who did some cool Japanese-monster inspired art!
I've done similar posts where I show how invertebrates have inspired pop culture. Here is the one I did for starfish awhile back..
It seemed like THIS year, it might be fun to actually show what some of the characters from Japanese pop culture (movies, TV and toys! actually LOOK like! (esp. with Halloween just a few weeks away)
GEZORA the giant cuttlefish from Yog-the Monster from Space!
Gezora stands 30 meters tall (98 feet) and apparently weighs 20,000 tons! Basically- a cuttlefish infected by extraterrestrial microbes! It kicks ASS! It first appeared in the 1970 classic "Space Amoeba" produced by Toho-the fine people who bring you the Godzilla movies!
Here's a neat slide show of various posters and screen shots from the movie...
from the people who broughtyou Godzilla! Gezora shows up at 0:50
This movie came out in 2004. Its about uh...well, a wrestler who becomes a giant squid! One great part of this flick? In the end he goes toe to toe with ANOTHER giant invertebrate! (no spoilers though!)
Japanese Cephalopod TV Monsters!
AMMONITE KAIJIN (Kaijin="Monster Man') from Kamen Rider Black!
A neat monster whose particular distinction was that the ammonite (serving as the monster's head) was kicked OFF his body early in the episode, leaving the rest of him wandering around and chasing after it!
The disembodied ammonite, in the meantime befriended a small child and learned the meaning of kindness. I don't make this stuff up!
And this neatSQUID KAIJIN from Kamen Rider Black!
For example, here is an ammonite "candy toy"-an item that usually accompanies a piece of chocolate or some other item (kind of the way a baseball card used to accompany chewing gum).
There is a series of these items that one collects and people sometimes hundreds of dollars to chase down a complete set of these...(the other items are mostly dinosaurs and other giant marine reptiles)
This represents an actual species of coiled shell ammonite-but not sure off the top of my head, which one it is..
Here is aLego ammonitethat I found how to construct here.
|Various shots of the snail Cyclonema feeding on the anal vent of the crinoid Glyptocrinus decadactylus from the excellent page of the Kentucky Paleontological Society|
So, today is National FOSSIL DAY! WOO!! and y'know, I figure WHAT do people WANT to see on National Fossil Day???
OBVIOUSLY the answer is PARASITES!! (and related stuff like commensals!) Everyone LOVES parasites! Especially echinoderm parasites! Its especially exotic when you can see them as fossils!
To be fair, some of the relationships below are probably better described as "commensal" which means that one derives gain from the host without the host losing resources..
What's often most exciting about these kinds of fossils is that we actually have DIRECT EVIDENCE of animal interaction! Which for the fossil record is often difficult.
We can see that fish had big bone-crushing teeth and we can even see broken snails nearby on a fossil deposit, but after 300 million years, you have to be careful about conclusions. This is often what makes good reliable evidence of paleoecology so valuable..
Here are 5 interesting cases of parasitism/associations/commensals on echinoderms from the fossil record! There are undoubtedly more...
Go here to see a neat free review account by paleontologists Tom Baumiller and Forest Gahn with a list of the many different cases!
1. Paleozoic Platyceratid Snails on Stalked Crinoids!
This one is probably one of the best known among fossils. Basically there is one Paleozoic group of snails belonging to the family Platyceratidae. They often look like this:
|From the TOL Crinoidea|
What the snails seem most interested in is the anal cone found on the TOP of the cup (this is the area where the mouth is found and is surrounded by the feeding arms). They are often found clamped down over the anus.
Most interpretations suggest that platyceratid snails are COPROPHAGES. That is a special kind of feeding which specializes on consuming POOP!
There are literally dozens of papers on the paleoecology and biology of these animals..and so I will leave this interaction to be written up in a later blog... But platyceratids are found on MANY different crinoids AND other stalked echinoderms from the Paleozoic, such as blastoids (see this account by Tom Baumiller)!
But that will be a story for next time...
|snail Cyclonema on Glyptocrinus from the Awesome Kentucky Paleontological Society page!|
This fossil was reported by colleague Christian Neumann (see his website here) and Max Wisshak from this issue of 2009's Palaeogreography, Paleoclimatology, Palaeoecology...
|Fig. 2 from Newmann & Wisshak|
These holes were compared against the kinds of holes made by modern day gastropods in the family Eulimidae which are often seen as parasites on starfish such as the blue Linckia laevigata shown here... (images by Sven DeVos on Flickr)
Christian Neumann and Max Wisshak have yet another paper in Ichnos (fr. 2006)!
This time showing how a shelled amoeba (i.e. a foraminifera also informally referred to as "forams") has parasitized the Cretaceous urchin Echinocorys (same species as the one above).
Their story here is this: Some forams will attach to an animals' shell or other hard bottom. Below is an example of one from the shell of a bivalve.
Notice how it leaves that prominent attachment scar on the right after its been detached...
|figure 2 from Neumann and Wisshak from Ichnos|
4. Symbiotic Relationship between a polychaete worm that bores into Cretaceous German Sea Urchins
And yet another paper by the industrious Max Wisshak and Christian Neumann in Acta Palaeontologica Polonica 51: 589-597! This one can be downloaded here!
Here Wisshak and Neumann document borings in the sea urchin's skeleton via the work of an industrious polychaete worm-a polydorid! Such worms bore though hard substrates and are asociated with tunnels such as this:
But how can you be SURE that these worms didn't just find the dead animal's skeleton and bore through that?? Why make the jump to "These holes were made in the animal when it was alive"???
This cartoon basically shows that following the worm's "boring" through the skeleton and the deformation of the skeleton by the worm..the surface spines and other structures- pedicellarie, etc. ALL REGREW over the area that had been "bored" through!!
|Figure 5 from Wisshak and Neumann|
Here are pics of the actual borings through the sea urchin test..
|Figure 2 from Wisshak and Neumann|
Finally! This neat account was described by colleague Hans Hess in the Journal of Paleontology recently in 2010! (click here for abstract)
|Image from South African Southern Underwater Research Group (SURG)|
|Fig. from Hess 2010|
Hopefully I'll get around to elaborating on those poop-eating snails some day!
|From J. Mallefet's Lab Page|
Their evolution is replete with adaptations to survival that are kind of mind blowing but as with all insanely unusual things, the ideas can be a little unsettling and frankly... a little SPOOOOKKKYY................
1. They don't seem to know when to die...
Most biologists have noticed that echinoderms don't quite die immediately when threatened with the kind of life-threatening injuries that many would consider life-threatening. Or else..its the WRONG part of the animal that seems to go on living... [Yes, some do regenerate (and that will be a subject for a future post!) but not all.] Some examples:
The Story of Stumpy
Here is a true story (although I don't remember who told me this story originally)
Years ago, following a lab accident or perhaps a crab run amok, the disk and 4 arms from a sand starfish (Luidia clathrata) was separated from the mid to end part of its 5th arm.
Contrary to popular myth, not all starfish can regrow a complete body from just the arm. This one certainly could not.
This separated arm tip (which was named "Stumpy") was kept in the water table and continued to move around for weeks to months...(I honestly don't remember how long but it was a long time).
Stumpy was even "fed" clams, which it apparently moved via tube feet to where it thought the mouth was. These clams would move up the tube foot groove and then just...fall out when it reached the disk location. No disk! (and thus no mouth)
It was never clear to me if Stumpy just sort of died on its own or if it creeped everyone out so much that they eventually just preserved it in the lab somewhere.
This isn't necessarily unusual "behavior." One can often observe the arm of a brittle star sometimes continue to move long after it is separated....
Presumably a combination of the unusual radial nervous system and the separated body part's ability to sustain itself using sea water (and nutrients) were responsible for this tenacious behavior?
But why believe an echinoderm zombie story when you can simply watch it...
Here is a "Zombie" Sea Urchin..The animal is broken open with insides removed and yet....IT LIVES
Sea Urchin Zombie from Timothy Ewing on Vimeo.
But on the OTHER hand.....
2. Uh... Do Echinoderms ever die of natural causes??
As a person who has worked in and out of museums and aquariums, one of the things you notice is how some species kept in captivity become bigger and bigger..
Some species such as Pycnopodia helianthoides (from the North Pacific coast)
|Photo by Allison Gong|
|Photo by Mr. J. Volz|
Now, to be clear-they do die. Diseases, aquarium mishaps, introduced predators and so on.
But under optimal conditions?? I have had people watching these cold water species live on for over 10 years (but I'll be honest I would need to verify) and more than once I've been asked "Do they EVER just die of natural causes??"
And honestly, I don't know if they do. Some accounts from the 1960s reported that they became "reproductively senile" but this account was speculative.
The idea of echinoderms as long-lived is not necessarily new.Here is a post I wrote back in 2009 about how ancient sea urchins can get.
So next time you go into say hello to a large sunflower star at your local aquarium-pay it some respect. It might be much older than you are...
3. Some of them GLOW in the Dark!
There is a whole POST worth of stuff on bioluminesence in echinoderms! And at some point in the near future I will write up more about it..but for now accept that a LOT of echinoderms glow!
|Image from J. Mallefet's lab page|
Most people seem to have a fairly benign impression of echinoderms. Harmless shapes that sit on the bottom of the sea floor that make up part of a dreamy seascape...
And just for good measure? Here's an earlier post featuring brittle stars that capture squid or fish if they come too close, rending it apart into pieces!! click here.
5. Dried Echinoderms are MUMMIES, NOT shells
This is probably one of the more macabre things that I've made note of before. Undoubtedly we have all seen starfish decorations for the holidays and weddings??
|A sad Pisaster ochraceus|
|sad Linckia laevigata|
Image by Alexander Semenov
Bonjour to everyone! At the moment I am continuing my research in Paris at the Museum national d'Historie naturelle! Here are a bunch of my prior posts about studying at this incredible place!
I'll be blogging more on this shortly but in the meantime, here are some neat close ups of various starfish species!
Solaster endeca (Pacific Northwest/N. Atlantic) click here to see what the animal looks like
Image by Alexander Semenov
Crossaster papposus (Pacific Northwest/N. Atlantic) click here to see what the animal looks like
Image by Alexander Semenov
Culcita novaeguineae (cushion star fr. tropical N. Pacific) click here to see it!
Plectaster decanus (Australia) Click here to see what the animal looks like
Image by Weedy Seadragon
Gomophia gomophia (Okinawa, Japan) click here to see what this animal looks like
Image by Okinawa Nature Photography
Nardoa sp. from the Indo-Pacific Image by sbailliez
Echinaster callosus from the Indo-Pacific
Images by Optical Allusion
the sand star Astropecten aranaciacus(temperate Europe, Mediterranean) click here to see it!
Note the star-shaped pillars are called paxillae. In theory they protect the papulae (aka the gills) from burial)
mage by fabbricmare
From a related starfish.. Gephyreaster swifti (British Columbia) More on this species here.
From Mediaster aequalis (west coast of N. America) a similar bunch of structures called tabula or tabular plates.. Click here to see it!
From an Australian relative of Mediaster called Nectria ocellata with some enlarged tabulae. It looks like this.
Image by ~aquaplane
Close up surface texture of the Indo-Pacific Archaster typicus. Learn more about it here!
More next week!
while not figured, here's a rather striking display jar for the 50-rayed Antarctic Labidiaster annulatus..
Often times, my research trips (and those of other scientists to the museum) fuse the old and the new. And go something like this:
There are any number of complications..
Types can be missing, analyses reveal unexpected results and of course new material is ALWAYS turning up in museums.. Sometimes new specimens can completely support a dubiously defined new species or instantly show how a recently described species is in fact just a variable individual of a known species..
Okay! But enough about work! Paris is a delightful city and I would be remiss if I did not share some of its charms..some not so subtle...
For example, this ammonite is already pretty cool "as-is"
Every good city has geology to be found in the unlikeliest of places... For example here is fossilifeous limestone used as floor stones on the Gare d'Lest train station..
Can you see the cross-sections through various shells and other invertebrates?? Unseen by thousands of persons a day??
Tucked away in various parts of the city are weird little fun moments like this one... (near Les Halles)
And where would we be if we didn't show some French food porn! Y'know what's amazing about this? The "pink" donuts in the US have famously adopted the description "pink flavor"..
But in Paris? not only can you get them warm-but they are RASBERRY. Tasty!
Some Turkish Delight...
And some very tantalizing cookingMacarons
We'll see you next week!
Go ahead and take a walk around inside a sea biscuit!
Judge, naturalist, geologist.
Gustave Cotteau made a career in the judiciary while devoting himself to paleontological studies. It was a judge in civil court Coulommiers civil court judge in Auxerre (1867), and retired in 1874.
As a scientist, he devoted himself to the research and study of living and fossil echinoids, which he had a collection of over 500 species. With numerous articles in newsletters and journals of learned societies which he belongs, he continued the publication of the collection founded by Alcide d'Orbigny in 1840, Paleontology French. He was curator of the town of Auxerre.
Secretary-General of the Institute of Provinces, responsible for publishing the reports of international conferences of Prehistoric Anthropology and Archaeology and the annual reports on the progress of geology and paleontology in France from 1858 to 1869...
Here's looking at you!
Image by the always awesome Arthur Anker! (Straits of Johore Biodiversity Survey, Oct 2012)
This week, owing to "crunch time" on my trip and being up to my arm pits in Antarctic starfish- you get a nice photo essay about sea spiders (btw-not arachnids) aka pycnogonids! Not echinoderms but arthropods!
Mostly of these are pretty tiny, which is why most people never see them, but the details are everything! I was told once by one of my professors many years ago that you could go your whole life and never see one of these-wow! times have changed...
From the Great Barrier Reef, Australia (probably Anoplodactylus sp.)
Image by Arthur Anker!
Some neat south African pcynogonids in the Florida Museum of Natural History collections
Image by Arthur Anker!
Shown this one before (from St. Martin) -but its amazing so here it is again!
A neat one from Grand Cayman. Image by CourneyPlatt
This one identified as Nymphon breviostre but not sure where its from... Images by Alexander Semenov
This one identified as Nymphon grossipes feeding on bryozoa. Image by Alexander Semenov
Pink and Yellow! From Australia. Image by Indr
Pallenopsis macneilli from Port Phillip, Australia by Peter Fuller
Yikes. This one looks overrun by wee sea spiders! Images by Alexander Semenov
Here's one of the deep-sea taxa, possibly Colossendeis. They get to be over 7 inches across! This one looks big.. Image courtesy of SERPENT Project
But what do Sea Spiders (Pycnogonids) actually look like alive and moving? here's some HD macro video for ya!
Sea Spiders from liquidguru on Vimeo.
And thanks to NEPTUNE Canada for reminding me about this neat video of a giant deep-sea sea-spider moving!
at the Universidade Federal do Ceara, Labomar but now at the National University of Singapore.
Arthur's photography stuns me whenever I see it and if I can share it with the public than I do! Enjoy!
and if you enjoy polychaetes go check out my link page of "bobbit worm" videos! here.
My post on the worm-shrimp 1-2 punch vs. crown of thorns starfish here.
Gorekia! the worm that lives INSIDE a sea urchin! here.
The Leather star (Dermasterias) scale worm love? story! here.
A gorgeous Trypanosyllis sp, a syllid worm from Moorea, French Polynesia.
A stunning Eupolymnia tube worm from the Caribbean
Head on with Diopatra sp. (Onuphidae) from the mudflats of Singapore
and more Diopatra love!
Eunice sp from the Caribbean coast of Panama
Nereis cf. riisei, rolled up into a spiral, fr. Panama
Fireworm (Chloeia sp) from Panama Canal
Branchiomma sp. a sabellid worm from Sao Tome, Brazil
Lepidonotus sp. from the Caribbean Pontogenia from the Great Barrier Reef, AustraliaA festively colored scale worm, Lepidasthenia sp. from Cozumel Island, Mexico
A neat pic of a sand-tube worm, Pectinaria IN a sand-grain tube! from the Great Barrier Reef, Australia.
Another Pectinaria species, from Florida showing the worm and its sand-grain tube
Finally, a maldanid polychaete worm from Australia
|Image courtesy of Chris Kelley, Hawaiian Undersea Research Labs|
Case in point-I have discussed how I have worked with the University of Hawaii and the Hawaiian Undersea Research Laboratory before. (go here to see)
|From the HUMMA Project website|
Specifically, I have been working with Dr. Margo Edwards in conjunction with the Hawai'i Undersea Military Munitions Assessment Project (or HUMMA) which is a coalition of institutions including the University of Hawai'i, NOAA, the US Army and others.
To put it briefly, there's a lot of unexploded bombs and munitions about 5 miles off the coast of the island of Oahu (and other locations throughout the Hawaiian Islands).
A nice video about this project is here:
And in factthe HUMMA Project has a Youtube Channel with a bunch of interesting things documenting their work here
In November the Hawaiian Undersea Research Lab (HURL) and the HUMMA Project took to the water with the submersible Pisces V (one of the only manned research submersibles still operating in the US!)
|From the Friends of HURL Facebook page|
|From the Friends of HURL Facebook page!|
|From the HUMMA Project website|
|Image courtesy of Chris Kelley, Hawaiian Undersea Research Labs|
And so, collections were made by the Pisces V submersible's collector arm..
Being able to look over the specimens at long last gave us two valuable discoveries!
1. Possibly a new species? The brisingids we were studying belonged to a genus that had never been seen in Hawaii before! And a species that could not be reconciled with any of the known ones! Further work remains to be done-but it seems like there is good reason to believe at least some of the brisingids studied belong to an undiscovered species!
2. What were the swellings? An examination of the swellings revealed an even more interesting discovery!! They were parasitic barnacles!!
There are some VERY unusual relatives of barnaclescalled Ascothoracidansthat can enter into the body cavity of sea stars (and other echinoderms), affix themselves to the internal body structures.
Some kinds of ascothoracidans have highly unusual relationships and can take over a host's reproductive system! (go here to see on case) It is unclear what the parasites in these brisingids do however.
The Time Lapse Project!
One part of the student's work involved engineering and developing their very own time-lapse camera for use in observing brisingid sea stars!!
Here is a video from their early efforts in shallow water Extended to night time...
And finally, here is the final product observing deep-sea brisingid starfish and some deep-sea sea anemones! Note how the brisingids move..
The full scientific impact and write up of all these discoveries is currently underway.
But I find it a hearty endorsement of these kids' abilities that they were able to develop such a clever and useful device given their constraints! This was something they did in high school! I look forward to their efforts in college!
A few weeks ago Ward Appeltans, who was the project manager for the massive World Registry of Marine Species database (here) collected and presented 121 contributors of various marine species, including some plants, protozoans and chromistans, fungi, some chordates and a WHOLE bunch of invertebrates!
The link to the paper is here. I believe it is open access until January 2013.
There are a lot of digests and news articles about this including these:
But of course in a "big picture" treatment, one often lacks some detail so I thought I would spotlight a department with which I was most familiar: Invertebrate Zoology at the National Museum of Natural History!
Eight out of the 121 contributors of the paper (that's about 6%) are residents/associates/employees of the Invertebrate Zoology Dept. at the National Museum of Natural History!!(part of the Smithsonian Institution)
|This graph from the WoRMS statistics page|
Some Neat Factoids about the NMNH Invertebrate Zoology Dept.
Its Christmas! I'm off to enjoy eggnog and awful movies but here's some bright colorful sea urchins for the holidays! Heterocentrotus from the Indo-Pacific (mostly Heterocentrotus mammilatus pics)
My best to all of my readers and followers for the holiday season!
Image by "backofthenapkin"
from Hawaii by weedmandan
From Hawaiian Islands. Photographed by Dwayne Meadows, NOAA-NMFS
One from the Red Sea. Image by vanveeleen
Here's another one from the Red Sea (maybe H. trigonarius?). Image by furstyferret81
A nice one from Hawaii. Image by Alan Cressler
One from the Sinai peninsula. Image by bluepeda
from Hawaii. mage by mbasile
from Hawaii by Arian durst
A close up by Geoff Spiby
Another Hawaiian one by chinds_1133
As 2012 draws to a close here are Five (of course) cool and awesome things that the Echinoblog enjoyed this year! These are not in any particular order....
1. MENTORSHIP! This year I mentored 3 kids from Iolani high school in Honolulu, Hawaii who studied brisingids (deep- sea asteroids). Their research was entered into the International Science and Engineering Fair and they were rewarded for their efforts!
2. THIRST DC. I gave a great and fun talk to a new social venue in Washington DC for the Smithsonian. Here's my brief outreach talk for the very gracious audience.
I'm always happy when something I do takes off and gets widely circulated this one did so in a pretty big way..
Deep Sea News (go here) and then later on by the Austrian Newspaper Der Standard (here) (this was in no small part to Miriam Goldstein! thanks!)
By the way the pictures from the US Antarctic Research Program (here) were WIDELY circulated and not always given proper credit. So let's remember that public research funded some of the interesting reading from here and here.
Other popular Echinoblog posts included:
1. Sand Dollars ARE Sea Urchins! Please make a note of it!
2. Sea Cucumber Evisceration Defense!
3. Sea Cucumber: Cuverian Tubule Defense!
4. Pedicellariae Diversity
5. The Anal Cone Controversy!
6. How Starfish Tube Feet work!
In the meantime, here was the big REVIEW article on asteroids I wrote with Dan Blake that is OPEN ACCESS from Plos ONE! Enjoy!
Okay you invertebrate zoologists out there!! How many phyla can YOU recognize on the plate above??? By the end of this blog you WILL know! (and maybe, you will hate me for telling you)
Everyone seems to have a "Weirdest foods" list out there-but here at Echinoblog we offer you only the STRANGEST sampling of bizarre marine invertebrates cuisine! forget insects, snails or shrimp!
Some of the edible (?) metazoans below are usually only noticed by marine biologists, zoologists and the well-studied biologist!
What better application of knowing the strangest of marine invertebrate phyla can there be than to recognize it on your plate? Its scientific name disguised by colorful cultural argot or perhaps in a different language?
1. SEA SQUIRTS! (probably genus Pyura?). The Korean name for sea squirts as food is: meongge (although there are several more)
Sea squirts are a kind of tunicate, which are in turn members of the phylum Chordata (the group humans and other vertebrates belong to) and when alive they look like this:
As it turns out, sea squirts are eaten all over the world, including Japan (called hoya and maboya) and Korea (meongge, and in a stew called agujim). They also eat sea squirts in France, Italy, Greece, and Chile .
Images of sea squirts eaten in Korea. Image by scbrianchan
A video showing preparation. Sea squirts are filter feeders and processing water through their body is a primary function. Thus, drainage seems to be an important feature...
when cooked and prepared it looks like this
or this.. Image by toughkidcst
sometimes served with oysters... Image by Food Fetishist
Flavor ranges from "rubbery" to something this..
2. ECHIURAN WORMS! aka "fat inkeeper worm" aka "penis fish" aka gaebul (genus Urechis)
Most people have never heard of this phylum of worms. Commonly known as "spoon worms"
One of the best studied examples is Urechis caupo, occurring on the North pacific coast -living in muddy burrows which serve as homes for many other commensals, including tiny shrimps and fishes.
But in Korea, a related species, Urechis unicintus is collected and eaten!
Apparently it is cut up into segments and served while twitching....
In other cuisines, it is cooked and stir fired..
the picture above? gaebul and mongae aka Echiuran and Sea squirt!!
and uh yeah, there's a belief that eating these imbues men with more virility. That seems unlikely....
3. INARTICULATE BRACHIOPOD (Lingula sp.)
Brachiopods are one of the oldest animals observed in the geological record, going as far back as 500 million years. In some cases-they appear relatively unchanged appearing very much as they do as fossils.
and now we eat them.
This gives you an idea of what they look like alive..living in a muddy habitat Image by Changhua Coast Conservation Action.
In one group, known as the "inarticulate" brachiopods, there is a big fleshy structure called the "peduncle" which emerges from the shell
Biologist Richard Fortey noted that they tasted like "straw' (quote is here).
Here is an image of brachiopods as sold in a food market in Makassar. Image by Arthur Anker.
Here is another from a Thai market. Image by Peter Roopnarine
In Malaysia this dish is called Probolinggo TEBALAN. The blog linked here suggests that Lingula tastes "sweet and spicy" whereas others I've seen suggest that it is served with a tasty curry.
Huh. Brachiopod curry. NOT something I was expecting to write today!
4. STALKED BARNACLES! Barnacles. Those well-known shelled crustaceans that live on docks and use their "legs" to filter feed out of the water like this:
These of course are what's known as "goose" or "goose-necked" barnacles because of the long, prominent stalk attached to the body sitting on top.
5. SEA STARS! (family Asteriidae- species: Asterias amurensis)
So, first let me distinguish between the "starfish for show" pictures that one sees around like this versus apparently real accounts of people who eat the gonads of starfish as seen in the video below..
Image by Robin G. Ewing.
Honestly, eating sea stars baffles me. And I recommend against it (as here) and here but obviously, people really eat these. On the plus side, Asterias amurensis (the species shown below) is a problematic invasive in Australia (as I wrote here)
so maybe there is a silver lining to this?
|Image by Viktor Lyagushkin. Gorogonocephalus from the White Sea|
Tiny little hooks on the arms are used to capture food which eventually makes its way back to the mouth.
Here's a nice video that shows their feeding posture in the wild
and a nice time lapse video of feeding from the Seattle Aquarium
There are currently 10 species of Gorgonocephalus recognized and they seem tooccur widely...(here to go to the World Ophiuroidea Database listing)
Here are some gorgeous Gorgonocephalus sp. (which occurs mainly in cold-water settings) images to kick off 2013!! Enjoy!
Some gorgeous shots of G. arcticus from the White Sea by Alexander Semenov
G. eucnemis from echeng (the "rose star" is the solasterid sea star Crossaster papposus) in Alaska.
Gorgonocephalus from Norway, 928 meters! Arms are tucked away...Image by SERPENT Project!
Several more on a ridge, using their arms to feed. Also Norway, 928 meters. Image by SERPENT Project.
More G. eucnemis from Alaska.. Images by jrixundewater
Close up of the arms..
An unusually pale, "bushy" individual from British Columbia. Image by Ed Bierman
Here's a really nice one of G. eucnemis. by "northwest diver"
Gorgonocephalus fr. Newfoundland. Image by Derek Keats
Newfoundland Image by Derek Keats
Hmmm... y'know, it never occurred to me before but Gorgonocephalus DOES bear a striking resemblance to a certain CRYSTALLINE ENTITY from the 24th Century...
So, between travel, being sick, yesterday's massive Inauguration Day festivities and playing catchup, this week has been crazy!
So here are some neat starfish time lapse videos to keep you informed and entertained!
The awesome video of the tropical shallow-water "chocolate chip star" Protoreaster nodosus, foraging for organic particles and other food on the sea bottom.
Stars of the Sea from Karin Brussaard on Vimeo.
The foraging behavior of the predatory Chilean/Patagonian cold/temperate water Cosmasterias lurida (Stichasteridae)
Some classic videos from the Shape of Life series showing behavioral complexity.Read this article frorm awhile back to see what's going on...
Echinoderms: Sea Star Time-lapse: Eating Dead Fish from Shape of Life on Vimeo.
Echinoderms: Sea Star Time-lapse: Don Wobber's Film from Shape of Life on Vimeo.
Here's a nice HD time lapse of a tiny aquarium asterinid starfish. Note stomach extended and the places where the algae is absent from the glass.
A day in the life of a starfish from Rate My Funeral on Vimeo.
An unusual video that shows what happens when you drop a bunch of Patiriella (bat stars) and let them run free! Starfish show up at about 1:19 (its mostly set up prior to that)
Here's a nice little vid showing Archaster typicus (different from Astropecten-you can tell between the two by going here to see the differences) in an aquarium burying itself into gravel
By comparison here is a species of Astropecten from Singapore doing its thing!
The giant Pacific sunflower star (Pycnopodia helianthoides) is fast enough that you can see it moving without time-lapse. What happens when you speed it up a bit?
Hopefully next will be all caught up and I'll be back to posting more!
|Image by Steve Corey|
|Image by "ratexla"/Josefine Stenudo|
|Image by Juncea|
|Image by Bárbol|
The top two pics (A+B) show an unattached tube foot.. But C through F? all show those attached to the bottom.
|Figure 1 from Hennebert, Santos and Flammang, 2012|
The authors indicate that suction may still play a secondary role, serving in conjunction with the adhesion/glue but for the most part it doesn't look like suction is a primary influence here.
2. Measuring the Attachment Strength of the tube feet
They tested the adhesion of the tube feet on glass relative to detachment force (how hard they pulled) and pulling angle (the direction). That is they tried to pull it off and at different angles on a smooth glass surface.
|fr. Fig. 3A in Hennebert et al. 2013|
B. Measure strength and tenacity on a porous bottom
Its possible of course that there are further refinements to how all of this works in sea cucumbers and crinoids but starfish and sea urchins have always been the "model organism" for studying tube feet in echinoderms.
Brittle stars are everywhere. They are the most speciose of all the living echinoderms with over 2000 species (probably MUCH more than that!).
At this moment in time, for studying brittle stars we live in a privileged time because we have several new workers who have taken to studying the various and weird lives of brittle stars!
One distinctive feature of brittle stars that researchers that study morphology have always known about are the unusual jaws present on the mouth of brittle stars. These jaws vary between individual groups of brittle stars. Its one of the fundamental ways that brittle star taxonomists tell them apart.
These jaws are superficially similar to the ones we see in other animals in that some of them have "teeth" (called oral papillae) and other features which distinguish them.
But other than their usefulness in telling them apart, what function do these "teeth" serve?
A recentopen access paper by Karin Boos, an author at the 7th European Echinoderm Conference held in 2010 (available here)addresses and discusses how the jaws might function relative to the feeding biology of two European brittle star species.
First off, Boos reviewed the feeding modes of two species with fairly distinct jaws and teeth.
One of the studied organisms, Ophiothrix fragilis is covered with many needle-like and bristling spines...
Images below by Hsacdirk
In life, they hold their arms up into the water and are almost always observed in this position in order to obtain food from water currents. Ophiothrix is a filter feeder.
They gather up food on their arms, which is then moved to the mouth via tube feet.
The other species studied was Ophiura albida which is more of a generalist. A sort of opportunistic feeder. Sometimes scavenging on dead animals but sometimes feeding on other smaller animals.
Each species has a different life mode and presumably the morphology, i.e., the teeth of each species reflects how each individual species lives.
|Image by Danielguip|
|Figure 1 from Boos 2013|
Boos takes some pretty nice profile images (her Figure 2) of the papillae (=the "teeth") that allow her to infer some function.
|top of pic is the oral surface, bottom is top or aboral. Fig. 2d-3|
It doesn't take much to take this consideration seriously. Here is some classic video from Neptune Canada showing what looks like Ophiura sp. fighting it out with another individual over some food.
and don't forget this blog about "brittlestars of death" as we saw Ophiura sarsii attacking mobile prey! (vertebrates even!)
Other related members also have jaws/teeth that sort of look like this. Maybe more of these are more predatory than we thought?
|Image by Arthur Anker|
|thanks to Wild Singapore!|
Feeding in Ophiothrix is nicely shown in this video. Food caught on the spines, is moved by tube feet along the arm to the mouth, where the food ball, called a bolus is devoured.
Ophiothrix and indeed ALL members of the Ophiothricidae are well-known in the taxonomic literature for having these unusually striking types of teeth.
Here's a close up! Usually with a very comb-like appearance... MANY papillae (ie teeth) on each "jaw"
There are LOTS more brittle stars where that came from... As I had indicated earlier, the "jaws" and "teeth" have been used heavily to classify and identify brittle stars but none were really good at understanding function...
Today a post about a NEW paper currently available as advance ONLINE at Marine Biology (yes, there's a paywall) authored by myself and Dave Foltz my colleague (with help from Scott Fatland) at Louisiana State University, and five multi-nationalcollaborators whose role will become clear.
This project originally began because we were studying a relationship between two near-Arctic sea star species. One in the sub-Arctic North Pacific (called Hippasteria spinosa) which occurs widely in Alaska/the Aleutians Islands, Washington, etc.
Hippasteria is a cold-water animal and is important as a predator of deep-sea corals and cnidarians. Here was a blog about some prior species I've worked on...
|Image by Davidtodd via Flickr|
|Image by Vidar - Aqua-Photos.com|
You can test the relationships between these species using genetics to determine if they are closely related. Sometimes you can even determine if they are literally the SAME species perhaps separated by time and the history of the region. Ice bergs and glaciers perhaps??
As it turns out, we found something intriguing...
The more we sampled these 2 species, the more we realized that scientists had assumed that Hippasteria was present from North Pacific to Arctic to North Atlantic.. it turns out no one had ever collected any from the Arctic!! (i.e., nothing in between!)
And to add more to the mystery, there were taxonomic accounts which indicated that there were accounts of the Atlantic species, H. phrygiana in unusual places..namely.. New Zealand!!
We looked at the distribution of this and related species..it turned out that H. phrygiana or species which closely resembled it were present all over the world!
A two-year effort on the part of myself and Dave Foltz was launched!
We managed to obtain samples of Hippasteria from all colleagues over the world! Our coverage spanned 3 oceans across 2 hemispheres!
We gratefully acknowledge all of the the co-authors and other scientists who helped us obtain the data we used in the paper!
What we found was pretty amazing. From all the populations around the world?
There was ONE species.
We extracted tissue and DNA from multiple populations and found that the genetic differences among the many populations found around the world were minute. SO minute that there was really no reason they should be regarded as separate species..
BUT there was structure. Different populations show SOME natural differences relative to other populations.
The following two diagrams show what's called "haplotype networks" for the two genes that we studied. The size of the circle indicates the sample size, whereas the different colors shows the region and the lines show the connectivity between the regions sampled..
|Fig. 2 Network for COI haplotypes|
We sampled two genes but I've only shown one network so that you get the idea. Basically, there ARE population differences between the populations in the North vs. South Pacific vs. the ones in the North Atlantic..
One Species Around the World!
You can think of this in the same way that human beings show differences (also called heterogeneity) between populations but are all basically considered the same species. In population genetics-its often the amount of difference between isolated populations that mounts up to indicating different species.
There's actually a LOT of animals that belong to only one species that are found all over the world (other than humans that is!)
Usually though, its small species (such as the brittle star Ophiactis) (see here) that get carried everywhere or perhaps things that swim like jellyfish...
BUT this is still kind of unusual. One species that lives on the sea bottom?? From a group of animals not known to be quick travellers or even particularly well travelled? This species' spread is probably via the marine larvae which were carried via ocean currents...
Widely distributed species often wreak havok with people who describe species (i.e. taxonomists). Do differences between populations mean many species? Or do they mean one species occurring widely?
In this case-its ONE species. This also has a pretty huge impact on taxonomy. In the old days, many species were identified as new because they were found in new places, or far away from where prior species were known. A lot of the technology to test these relationships was not yet available...
But now that we know, ALL those species names that fall within the range of our study will be suppressed (via international rules) by the oldest name-Hippasteria phrygiana. So, for example, the North Pacific Hippasteria spinosa (described in the 20th Century) will now be called H. phrygiana (described in the 19th Century) because they've been shown to effectively be the same.
Another spin- HOW FAST did they Spread Out? and from where?