Monday, November 30, 2015

Imaging Brooding Brittle Stars Babies!

Greetings! So, today I am en transit from my month long research trip in Paris back to home base in Washington DC!  So, in the meantime I thought I would share the results of this great new imaging project presented in GigaScience by some colleagues at CapeTown University in South Africa whom I met while I was visiting a few months ago!!  Jannes Landschoff, Anton duPlessis and Charlie Griffiths.

Their study actually surveys THREE species of brooding brittle stars!

What does this mean? In MOST echinoderms,  following fertilization juveniles pretty much settle out on their own and are left to grow/rear out on their own. But in some unusual instances there is actually parental care! 

So, yes, some adult echinoderms rear juveniles! Yes! Baby echinoderms! I've detailed this behavior in starfish in some detail here.   and of course, who can forget the life and death struggle of tiny asterinid starfish hermaphrodites who attack and eat one another in the "womb" of the mother?? (here)

Jannes' study focuses primarily on three brooding species in the South African area, including Amphiura capensis, Amphipholis squamata (both in the Amphiuridae) and one called Ophioderma wahlbergii

Jannes' work was actually surveyed here in GigaScience's own blog  Jannes and co authors use three dimensional visualization tools, including x-ray micro tomography scans to unobtrusively visualize brooding juveniles without destructively sampling the original specimen. Neato!

This gives you an idea of what Amphiura capensis looks like..
Image borrowed from Eastern Cape SCUBA diving! Go check em' out! 
Here's a visualization with CT Scan from Amphiura capensis!
which you can see more of here on this video

Jannes' study images brooding (i.e., the behavior of retaining the juveniles) in cavities called bursae which are located in the regions between the arms within the disk of the animal (in blue)
Here we have some just SPECTACULAR imagery of brooding in Ophioderma wahlbergii!
As it turns out, this will probably be a useful tool for non-destructively studying other brooding brittle stars and other echinoderms!

One South African brooding starfish (different from brittle stars) species which we know almost NOTHING about?? The South African "slime star" Pteraster capensis!  
Brooding cushion star, Pteraster capensis

and there are a MANY species of brooding brittle stars to choose from...

and this aptly named brooding species...Ophiacantha vivipara (from Rafael Martin-Ledo's neat but shortly lived Antarctic blog!)
Congrats to Jannes & my colleagues at Cape Town University for their new paper and looking forward to hearing more about their interesting future research! 

Wednesday, November 18, 2015

Paris! Urchins in Abstract!

This week: more showy echinoderms from one of the greatest museums in the world! Paris! Here's another study in abstracts-focusing mainly on sea urchins!

Last week was all about starfish mouths & their spines, etc.

I've blogged before about sea urchins from Paris. Here's one...

and an older one..

And a similar type of blog from my visit to the natural history museum in Tokyo! 

Alien landscapes? Weird colors? Vs. Spines, mouth plates and sea urchin skeleton! Enjoy!

The duo colored spines of the urchin Salmacis
The "teeth" of a "pancake urchin"

Oral spines on this cidaroid urchin. Yikes!
The naturally orange colored spines of this cidaroid (Compsocidaris?)
Natural green and purple stripes on these urchin spines!
More green and purple colors on this cidaroid urchin!
The large crazy spines of Goniocidaris and what lies beneath! 

Monday, November 9, 2015

Paris 2015: The Starfish Mouth in Abstract


Bonjour and Greetings! My apologies for missing a post last week! I am currently on a research visit at the world famous Museum national d'Histoire naturelle in Paris! Between jet lag and getting my work set up, things got away from me!                                                                                     
This week, A collection of starfish mouths! Echinoderm anatomy often fascinates people. The symmetry is one reason, but also the very intricate architecture and unusual textures. 

Here is a collection of close ups and abstracts from echinoderms in the Tokyo Museum.

Here's an assortment of mouths & mouthparts from the collections of sea stars in Paris! I see the adaptations for survival in these structures.

Spines serve a protective function in many species but are also part of how the animal feeds. The full range of how these structures function is not clear. In contrast, other mouths are surrounded by granules or plates presenting a somewhat different interpretation.

but certainly.. these might even evoke more artistic interpretations from others!

Euretaster, a tropical slime star. Spines galore!
From Luidia, a multi-rayed sand star
From the Antarctic Odontaster.. note the big "teeth" on each plate. These are thought to function in sponge predation.
Protective mouth plates on Lithosoma
On a tropical oreasterid
On the sand star, Astropecten
 On a "cushion star" Peltaster placenta
From the tropical cushion star Culcita novaeguineae
A deep-sea mud star, Plutonaster
 Deep sea goniasterid, Nymphaster
 A deep-water oreasterid!