Wednesday, June 15, 2016

Sea Urchin Biomimicry! Echinoids Inspiring Applications from knives to glue!

Tiny teeth
Its been awhile since i've done a "What have we learned from Echinoderms?" type post.. So, this week a news round up about the utility of sea urchins and their inspired applications!

Although I talk about several different inspriations, two of the stories below focus is the elaborate jaw mechanism in sea urchins known as Aristotle's Lantern! A nice basic definition can be found at the Echinoid page on The Natural History Museum in London (here). 

Aristotle's Lantern is this weird yellow piece in the picture below. These sit over the mouth opening and the "teeth" or jaws of the sea urchin emerge through the bottom..

This illustration gives you an idea of the orientation

Image from page 201 of "Elementary text-book of zoology" (1902)

And here's a video that allows you to see the teeth emerging through the oral opening and back again. 
Urchins use these teeth to rasp algae and other food off the substrate. They are quite effective when one considers just how much algae a sea urchin eats!

ALL of the stories below are part of a field known as biomimicry!

Basically, taking the idea/engineering from ACTUAL biological structures that have demonstrated effectiveness and reverse-engineering them so that they can be used in industrial or other applications!! Urchins have been quite the inspriation of late! Here's a round up of some of the recent and more interesting ones!

1. Self Sharpening Blades/Knives! 
Based on this account in Advanced Functional Materials and a summary in National Geographic (here) sea urchin teeth were studied with x-rays and determined to occur in separate layers with different structural textures which are interlaced between softer organic layers.                                       
One of the textural layers breaks very easily but is also replaced very easily. These areas get "torn away" whenever the teeth on sea urchin jaws are used.. but are also replaced quite quickly! 

Thus, functionally, the teeth grow continuously and are thus CONSTANTLY being rejuvenated and are essentially always sharp! 










2. Sea Urchin Jaws Inspire Space Exploration??

You can also just watch this video account of the whole thing...

Here's an Italian "bionic model" of how the Aristotle's Lantern jaw might work.. Kind of similar to the way a claw in one of those arcade "grab claw" games works! 



3. Architecture: Urchin Test Shape distributes Stress! 
Its been commented upon at sites such as these that the "oblate" shape of sea urchin skeletons (i.e., the test) is very effective at distributing stress evenly over the surface. Thus, the shape of urchin skeletons might actually be useful for inspiring better shapes in building! 
urchin test
...and then of course, there's the TARDIS in Doctor Who! 


4. Sea Urchin Spines Inspire Idea for Concrete! 
A paper by Seto et al in PNAS from 2012 studied the physical structure of sea urchin spines and discovered that they were composed of crystals that were bound together with a second type of calcium carbonate, acting as sort of a mortar, but with no crystal structure. These give the spines a highly resistant texture that suggest a better way to make fracture resistant materials.  A summary of this was in this BBC story.  and yet even more can be found on this blog about Mesocrystals and concrete! 
Sea Urchin spines
5. Adhesives!
Amazing sea urchin tube feet

Instead of "suction" as had been believed for decades, it turns out that urchin tube feet work on a chemical adhesive basis! In other words,, they STICK instead of SUCK!  You can go through a brief summary of these details here. 

These provide a lot of potential for marine adhesives if the means of adhesion can be understood and "reverse-engineered"!

Other posts in the "What good are echinoderms" series to be found HERE   
and here

Wednesday, June 1, 2016

Echinoderm Research at Museum Victoria! So long and thanks for all the Starfish!

Tropical brittle stars (2)
In the same way that a particular class of echinoderms is made up of diverse members, so are the research labs which study them!  So, in my last installment of #EchinoblogInAustralia I thought I would do a brief profile of researchers doing various kinds of echinoderm research at Museum Victoria in the Marine Zoology Department!

I've done similar profiles for the researchers in Paris at the Museum natioinal d'Histoire naturelle (here)! I think this gives everyone a bit of insight into the many different crew members which staff the various roles in the big research seen in scientific papers. And Dr. Tim O'Hara's lab has had a good week for "big research paper drops" with more to come!!

Just as a refresher though.. Here's a pic with the BIG project that Tim O'Hara's lab has been working on for the last several years: the BIG ophiuroid (aka the brittle and basket star) phylogeny! aka the "family tree" of the ophiuroids!

As I've mentioned previously, the new phylogeny is a BIG deal. It involves a group with over 2000 species which has been a taxonomic headache to scientists for over 100 years. Their research has literally turned this whole field on its head! (if brittle stars had a head!)

The tree clarifies which groups show support for being "real" and elaborates on how different brittle star and basket groups are related to one another.  It will almost DOUBLE the number families!!!
The tree itself is HUGE. Here it is below printed out and mounted on the wall for easy reference. You can see that it extends from that lower bookshelf to the that top shelf-so the printout is easily 6 feet tall (or two meters)!!

The tree was made using a phylogenomic data set. This is different from a lot of the molecular trees made in the last 20 years because it includes a whopping 425 genes and over 60 taxa! (other trees generally use only 3 to 10)  You can see the big paper as published in Current Biology here.

The Echinoderm researchers at Museum Victoria includes a diversity of workers!

1. Dr. Andrew Hugall
Where Tim O'Hara provides the "Ophiuroid Taxonomy and context", Dr. Hugall is the phylogenetics and analytical guru part of the "Big Ophiuroid" team. Although he is currently working on marine invertebrates, he worked previously on birds, discovering "Accelerated speciation" in highly colorful birds, a paper which was published in Nature in 2012. You can see that here. 
Dr. Hugall worked on the analytical aspects of the project and, in conjunction with Dr. O'Hara, cleaned up the genetic data in order to make it ready for analysis. He also provides a good complement to the "natural history" side of the lab with a powerful analytical background.

2. Lupita Bribiesca
Lupita is a PhD student at the University of Melbourne and got her undergraduate degree from the Universidad Nacional Autónoma de México. She's not only very proficient in computer coding and analysis but she's already a prolific author in echinoderm systematics! Especially in anchialine cave echinoderms!
In Mexico, Lupita worked on echinoderms which lived in submarine caves fed by the ocean. Some of her work can be found




3. Skipton "Skip" Woolley

Skip is a relatively new name on the echinoderm scene! But started out in grand fashion! His name of course headlines last week's BIG NATURE paper on ophiuroid deep-sea diversity! (here)

He's been doing analytical work looking at "big picture" diversity patterns in ophiuroids. His prior paper looked at biogeographical subdivisions in Western Australia in the journal Diverstiy & Distributions

4. Dr. Kate Naughton
I featured Kate Naughton's work on the blog back in 2009 when she and Tim O'Hara discovered a brooding "cryptic" species of the Australian Biscuit Star Tosia using molecular tools to understand the relationships of Tosia australis along the Australian coast. (see this story here)

Since then Kate has received her PhD and continued to do her awesome work combining ecology, taxonomy and molecular phylogenetics at Museum Victoria.
These days she's been working a LOT on feather star (i.e., crinoid) taxonomy and diversity in Australia. It turns out that there's a LOT of these in Australia that remain to be discovered and what's known requires a lot of work. 

As with many of us, she seeks a good job, funding for her research and all of life's finer things!

She HAS however also been working on new species of brittle stars in the genus Ophionereis
photo by John Keesing

















5. P. Mark O'Loughlin and Deep Sea Sea Cucumbers
One of the most established echinoderm researchers at Museum Victoria was actually Tim O'Hara's original mentor!  

Mark O'Loughlin has been a fixture of the "marine invertebrates" scene in the Melbourne/Victoria area of Australia for decades. He's published a huge volume of work on echinoderms,  including sea stars and sea cucumbers. Here's his profile at ResearchGate! 

here's a sclerite from a new species of "sea pig" (Family Elpidiidae) that Mark is currently working on from the the Great Australian Bight (979 m)
Mark has been working steadfastly into his 80s but has assisted by many student workers (one of which is seen here)

My thanks to the Museum Victoria for my visit! About 1000 specimen lots identified! 
Until NEXT TIME, Melbourne!! 

Thursday, May 26, 2016

BEHOLD: The GAME OF THRONES BRITTLE STAR! & new ophiuroids from New Caledonia!


As many of you picked up on last week, I've been busy working on starfish at Museum Victoria in Melbourne working with my colleague Dr. Tim O'Hara, one of the world's leading authorities on ophiuroids! aka the brittle stars and basket stars!

He's had a BUNCH of big research news drop lately (here's the link to last week)

While talking to Dr. O'Hara he informed me of of some neat, NEW SPECIES he's described from the deep-sea habitats of the South Pacific New Caledonia in late 2015! These were just too neat to pass up a post on!

I've reported in earlier posts (here) about working with Dr. O'Hara on echinoderms in the Paris collections! 

All of these species were published in the Memoirs of the Museum Victoria, vol. 73: 47-57 published in 2015. Co-authored by Caroline Harding, also at Museum Victoria!  This article is OPEN access and can be downloaded HERE. 

1. The Impeller Brittle Star


As Dr. O'Hara tells the story, he was once called upon to aid a ship's engineer during his attempted crossing of the Bass Strait on the yacht Irene. A similar looking impeller failed the yacht's engine thus indelibly impressing its shape onto his mind's eye!
                                                                                                                     
Fast forward many years.. and Dr. O'Hara is describing this new amphiurid brittle star from the deeps of New Caledonia.

The large shields on the disk trigger a memory that reminds him of the impeller's shape! and voila! 
Enter: Ophiodaphne impellera 















2. The Game of Thrones Brittle Star: Ophiohamus georgemartini!!
Probably the most STRIKINGLY amazing brittle star Dr. O'Hara described was this one, a new species in the genus Ophiohamus (family Ophiacanthidae), collected from a depth of 275 meters off New Caledonia!

Here's a nice shot of it holding onto this sponge stalk... Note that its most striking feature? Those big crazy spines that are coming off the disk!

If we take a closer look at those big thorny spines coming off the disk...
and compare them with the sharp thorns coming off the crown depicted on the cover art from Game of Thrones: CLASH OF KINGS!                                                                 This provided the inspiration for the Species name for THIS new species of brittle star!        
BOOM! Tim named this one in honor of the AUTHOR of one of his favorite shows: GAME OF THRONES!! 
Ophiohamus georgemartini!! 

3. Ophionereis sykesi (family Amphiuridae) in honor of his wife who as Tim O' Hara put it "has had to put up with him rummaging around the world's museum collections for years"

An animal with a gorgeous disk plate field which I'm sure is a fitting honor for the Mrs! 

4. And finally, Amphipholis linopneusti, described by Dr. Sabine Stohr in 2001.  

NOT a new species but an interesting one from the New Caledonia region in that its one of the few echinoderms that I know of which is actually sexually dimorphic!  That means there are actually ways of determining males from females using external characters! 

The lowermost basal arm spines of males are enlarged, sometimes flattened and hour-glass-shaped, whereas on the females they are cylindrical with a blunt rounded apex.  Its a subtle difference to be sure but it exists, which is more you can say for a lot of echinoderms! 


Wednesday, May 18, 2016

BIG DATA about SMALL Echinoderms! Ophiuroids & their HUGE impact!

Image by Dr. Julian Finn, Museum Victoria
If you had asked me 10 years ago if the echinoderm group we would be learning the MOST from would be the OPHIUROIDS I would have been skeptical.

Basket stars? Taxonomy was impenetrably difficult. 
non-Basket stars? even worse.

Plus, Brittle stars were tiny, numerous, CRYPTIC animals. Who would study them? 

I'm sure we would see "big picture" stuff from sea urchins, sea stars or maybe even crinoids. But brittle stars? It would take a LOT of work to make them an "ideal" animal to work off of....

This week a BIG NEW PAPER in Deep-Sea Brittle Stars dropped in the pages of NATURE

I'm sometimes quite happy to be proven wrong! 



The paper from Tim O'Hara's brittle star lab at Museum Victoria in Melbourne, Australia, written by Skipton "Skip" Woolley et al. comprehensively analyzed 165 THOUSAND distribution records of brittle stars!!  

In other words, Tim identified, requested and/or otherwise retrieved THOUSANDS of records of brittle stars! When you consider how MANY specimens of ophiuroids there are? That is a HUGE effort!! 
Based on this analysis of species records correlated with different habitats, especially across different depths, they were able to determine several broad based and IMPORTANT patterns about WHERE brittle stars occur..
  • Deep-sea species diversity is shaped by energy availability (i.e. thermal energy and nutrients)
  • Continental shelf to upper-slope species richness consistently peaks in tropical Indo-west Pacific and Caribbean (0–30°) latitudes, and is well explained by variations in water temperature. 
          In other words, warmer water (heated by the tropics) promotes greater species richness. 
  • Deep-sea species show maximum richness at higher latitudes (30–50°, i.e. polar regions), where they are concentrated in areas with high carbon export flux and regions close to continental margin (richness drops as you get away from the land).
  • Ophiura sarsi
  • Global brittle star richness, in terms of species, peaks in the tropics at "shallow" continental shelf depths (20-200 m) and upper slope depths (200-1200 m). These peaks drop when you get below 2000 m depths. 
           The yellow and red in the diagram indicate species richness. These are warmer areas with                    relatively high nutrients, etc.  As the colors fade to purple and blue we see those numbers    
           decrease on the broad abyss of the ocean floor.

  • Data are consistent with a hypothesis that deep-sea species richness is maintained by species migration from shallower regions. i.e., "high energy areas feed low energy areas"
  • Historically we have looked at tropical areas as the focus of conservation efforts, but if we TRULY want to conserve deep-sea habitats we will need to consider the areas which show DEPENDENCE on the shallower regions for diversity.
If this is the case, then our conservation efforts will need to focus on MORE than simple high species diversity. We'd need to further look at places which are DEPENDENT on diversity!

In some ways, brittle stars are one of the most important "model animals' to observe these trends and interactions. Why?

1. Echinoderms, including brittle stars live ONLY in the oceans. No freshwater, or land relatives.

2. Brittle stars are EVERYWHERE. They are one of the most numerically abundant groups of echinoderms known.
PB230486 Amphipholis squamata 

This paper is the latest "big thing" to come out of Dr. Tim O'Hara's echinoderm lab at the Museum Victoria! 

The Nature paper is sort of the "other shoe" that has dropped with big discoveries. (Remember that
echinoderms have five shoes!)

Dr. O'Hara's other BIG news  in recent years has been the announcement of this: a comprehensive family tree of the ophiuroids! 

The Brittle Star Phylogeny Project
One of the most important and fundamental elements of biology is understanding the evolution and relationships of your study organisms. 
  • How are all the different groups related? (e.g., how are basket stars related to other brittle stars?)
  • How did they diversify? Where? 
  • What kind of habitat did they diversify into? 
  • Which brittle stars form actual, NATURAL biological groups? 
A phylogenetic tree helps to answer all these kinds  of questions! 

In biology, a well-supported tree with a strong data set supporting it is BIG DEAL.  You can literally put ALL the information known about a group, in this case-the brittle stars, into a PROPER evolutionary framework!! Perhaps some lineages share a particular ecological nice mirrored by body form. A tree like this can literally be mined for information for years. 

This starts with such immediate things as classification and rearranging all the families to reflect "natural" groupings. In other words whether taxonomic groups such as families or genera-created by scientists based on external characters are "real" or perhaps the result of misleading external appearance. At some point, there's probably a whole POST about that topic!

This kind of data is a POWERFUL statement.

Genetics is powerful stuff. Work on the "Big Tree" of ophiuroids suggests that there are many, MANY more families and SEVERAL orders of magnitude more SPECIES.

Past accounts have estimated about 2000 species?  In fact there are likely several TIMES MORE than that. But the exact number remains to be seen..

The work from Tim's lab has nearly DOUBLED the number of recognized FAMILIES of Brittle stars! 

He's also turned the classification of these animals on their head! some of the oldest known species turn out to be these interesting deep-sea forms.. Ophiomusium and their relatives! Many surprises!
image from Museum Victoria: http://researchdata.museum.vic.gov.au/brittlestar/www/o_lym.htm
You can sort of see how this ties in with the brittle star distribution paper.. How many of these points on the tree will show relationships between deep-sea and shallow-water species??

These efforts are some of the latest results from Tim O'Hara's "Big Data" ophiuroid work!

Remember that the fundamental basis for ALL of these projects has been Tim's skill in TAXONOMY of brittle stars. Many of these species were difficult to identify and reconcile without skills in how to tell them apart.  Here was an account of Tim's work at the Museum national d'Historie naturelle in Paris! He identified over 1000 specimens while I was there.

Other past efforts from Tim's lab:

Here's
 the time he and his student worked on the mystery of cryptic species in the Australian biscuit star Tosia australis


Here's his research on discovering the distribution of brittlestars in lateral bands

We'll be seeing more on Tim's lab NEXT WEEK! As Echinoblog continues on in AUSTRALIA!! 

Wednesday, May 4, 2016

Five IMPRESSIVE HIGHLIGHTS from the Okeanos Explorer's Marianas Expedition!

This week I do a brief recap of spectacular views from the Okeanos Explorer Expedition to the Marianas Islands which began earlier this week. You can find out all about it on their website here.
Long story short, they are in the tropical North Pacific near Guam with access to some of the deepest trenches and canyons in the world!

This first leg began on April 20th and continues until about May 11th. They have been surveying many very deep canyons and seamounts which are at best, very poorly known and reach 5000 m depths or so!

Many, MANY amazing things have already been seen during the last seven days or so. Here's a recap of the things I thought were most fantastic. But check out their blog here.

Remember that the live video is broadcast here (via Youtube). The live broadcast begins fairly late if you are on the east coast, but usually around 5 or 6 pm.

You can also find many of these images from screengrabs on Twitter using hashtag #Okeanos or go to the Facebook underwater screengrab group here. 

1. STUNNING Gorgonocephalid Basket Star Fields
So, on May 2nd, the Okeanos Explorer visited Zealandia Bank, in relatively "shallow" depths about 650 to 250 meters. 

While surveying this area they discovered this AMAZING field of basket stars!! Apparently in the family Gorgonoceaphlidae. You can read one of my earlier accounts on other members of this family live and feed here. But short story: they have elongate arms with hooks that capture prey carried on the water currents.

At this amazing site we had...HUNDREDS  of these animals as part of a community of filter-feeding aniamls.
Here's what one looks like closer up.
But again, just spread out EVERYWHERE. At one point Diva Amon, the biology science lead indicated they had travelled about 100 m seeing basket stars to no end!
The animals in this area were all taking advantage of the current flow, including these isocrinid stalked crinoids and those little white corals.

At one point they mentioned that the water current above this field was about 1 knot, which means that the "drag" of this current against the bottom created a good habitat for filter feeding animals.

This area included other species of invertebrates.. starfish and so forth, which could have been feeding on the filter feeders or perhaps indirectly taking advantage of other benefits from the current flow (food, etc.).

Personally, this one was my FAVORITE thing to have seen. Just amazing.

2. Hydrothermal Vent Chimneys 
On May 3rd, Okeanos went to a suite of amazing hydrothermal vent chimneys!!!  These are places where hot geothermally heated water is vented out through the earth's crust. The dive went down to about 2000 to 4000 m. VERY deep.

This leaches out hot water with toxic minerals into the surrounding water. Surprisingly however, there are a great MANY animals which are able to process these minerals into food!

On this site, it included specialized limpets and other snails, as well as bythograeid crabs, shrimps, polynoid polychaete worms and much more! (as well as bacterial mats growing around the hot water and etc.)
But perhaps MOST impressive was how these vents formed chimneys which took on these very cathedral-like morphologies.

Stunning.

They pretty much spent the whole day going from one chimney to the next..and none were disappointing!



3. Likely New species of Carnivorous (Cladorhizid) Sponges
Probably some of the most commonly encountered animals on the Pacific Okeanos expeditions have been sponges (here for more). Chris Kelley at the Hawaiian Undersea Research Labs has mentioned that there are easily two dozen new species of glass sponges currently being described with more apparently being discovered!

But one of the more unusual sponge species discovered on these cruises are those in the family Cladorhizidae: enter the CARNIVOROUS sponges!!  Although they've been known to scientists for awhile, they only recently entered the public eye after the famous "Candelabera sponge" was discovered back in 2012. 

Cladorhizids occur pretty widely as it turns out. Here were two discovered by Okeanos Explorer during the Okeanos leg of this expedition.. Both collected and are probably new species.

Bizarre spines on this one...
This image shows some small amphipods and/or possible food caught on those spines...
This one has a very different body shape with more club-shaped projections....

4. Likely New Stalked Crinoid species!
Stalked crinoids are some of the most... evocative of deep-sea animals, mainly because of their status to some as so-called "living fossils."

Animals with similar morphology are well known from VERY old rocks (back to the Paleozoic) go here. And although these modern forms are different from those fossils forms, they DO share a certain similarity.

I ran these by some of my colleagues (who are stalked crinoid experts).. and this one for example was described as "totally crazy"

This one was apparently seen before from the Philippines/Celebes region and was identified as a new genus and species! All we have to do now is to collect it!

5. Impressive Acorn Worms (enteropneusts)
Acorn worms are one of those weird groups of worms that have been around for quite awhile and are known to biologists but only recently has there been very good imagery to show off how cool looking they are!

Some of the more striking deep-sea species were recently presented by the Monterey Bay Aquarium Research Institute back in 2011! see this) One Atlantic species of these worms was actually named for Star Wars Jedi Master Yoda! based on the large "ears" (actually genital flanges!) 

Okeanos saw this one recently, displaying a prolific amount of mucus and a very prominent amount of defecation as it plows through the sediment feeding on the organics!

Here we see mucus with sediment granules as well as poop inching its way long the intestine...

Let's face it, there has been a LOT of amazing stuff on these dives...


Honorable Mentions
This fantastic benthic ctenophore! I've discussed these in many posts before (go here) but this is a bottom living species of comb jelly, which are normally observed swimming...

They extend their very LOONG tentacles into the water to feed....One individual measured during the hawaiian expeditions went on for nearly a meter! 
This was a mystery. A bunch of soft, blobs. Still not sure what it is (foram? sponge? eggs?)..but enigmatic and intriguing.
This sea urchin popped up during the last hours of the hydrothermal vent dive (see aforementioned vent chimneys). A bit of a mystery....

And then yesterday near the mud volcano, we observed not just this large star-shaped trace mark in the sediment but ALSO this little brittle star!

Note how the disk has a kind of raised dark bump?? That's a feature that is pretty unusual for brittle stars. So possibly in the genus Ophiomyces or something else which could be entirely new..

If so, this would be one of the first times its been seen alive! 

Predatory Tunicates! 
These are actually Chordates like us, but usually tunicates are filter feeders that pick organics out of the water current..

HERE we have TWO genera of tunicates which have adapted to feeding on other ANIMALS!

This one is called Megalodicopia! These have modified their "in" siphon to form a HUGE mouth. Note the little tube on top?? That's the "OUT" siphon. Water goes, with food and flows out through the top (presumably at a higher pressure given how much narrower it is).
Another stalked predatory tunicate is this one: Culeolus. Same basic idea, except that the feeding bits are on a STALK... Water+food goes in one end and out the other!!

and of course, this beast!  yeah, yeah, the jellyfish, Crossota sp... always a crowd pleaser!