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24 Oct 11:38

Hybrid speciation might be rare

by whyevolutionistrue

Data show that the “normal” mode of speciation—the process in which one lineage divides into two or more species—involves the geographic isolation of populations of a single species. Over time, natural selection (and genetic drift) causes those populations to become more and more genetically different. When the genetic differentiation has gone to the extent that the separate populations evolved features that make them unable to produce fertile hybrids when they come back together in the same area (i.e. regain “sympatry”), then these populations have become separate species. They are now groups on distinct evolutionary trajectories, and their inability to exchange genes because of the evolved “reproductive isolating barriers” between them (e.g., behavioral differences in mating, preferences for different host plants or microhabitats, different times of mating, different pheromones, or the sterility or inviability of hybrids), is what makes nature “lumpy” rather than a continuum. The lumpiness of nature—the fact that, in a single geographic locality, in most groups you readily see distinct clusters of plants or animals (look at the birds outside your window, or look at a field guide)—is an important fact that can only be explained by connecting the formation of those “lumps” with the reproductive barriers that keep them from forming a continuum.

Geographic isolation is thought to be important because gene flow between diverging species tends to keep them from diverging. In our own species, humans in different places began the process of genetic divergence, as witnessed by the traits that distinguish human populations (these are correlated with geographic isolation, as the theory predicts), but this process was nipped in the bud by both population growth and the invention of forms of transportation that allow people to move much farther than they used to. There is now gene flow between many populations, and Homo sapiens is an example of a “polytypic” (variable) species that, if the populations had remained isolated for a million years or so, might have become more than one species of Homo.

One thing that biologists have discovered since the advent of DNA sequencing, though, is that gene flow between species is more common than previously thought. Reproductive barriers aren’t always complete (although they are now between our species and all other living species), and so sometimes hybrids are formed and genes can sneak between different species. In the group I used to work on, the closely related species Drosophila santomea and Drosophila yakuba, we and others discovered that the entire mitochondrion, with all of its own DNA, invaded D. santomea from D. yakuba, and there’s been a bit of other gene flow as well. (In most of the genome, however, the species remain distinct.) This could only have been due to hybridization, and it happened because although the species tend to live at different altitudes, there are areas of overlap where they can meet and hybridize, and the female hybrids (but not the males) are fertile.

So we know that genes sneak between species more often than we used to think.

Some biologists, however, have gone farther, and postulated that hybridization between two species can itself cause the formation of a third species, a process called “hybrid speciation.” This is somewhat common in plants, occurring through a special genetic mechanism called polyploidy. There are two forms. Allopolyploidy involves the hybridization of two species having different chromosome numbers, and since the different chromosomes can’t pair in the hybrids, those hybrids are sterile. However, if the chromosome number doubles in the hybrids, so that a new individual is formed with a chromosome number equal to the sum of the numbers in both parental species, one can get an “allotetraploid” populations whose members are fertile among itself but sterile when they mate with either parental species. (See any evolution textbook for an explanation.). This would, then, be a new biological species.  A similar process can occur if chromosome number doubles within a single species, producing an autotetraploid. Further hybridization and chromosome doubling can lead to entire polyploid series of plants with hundreds of chromosomes, as in ferns.

As I said, polyploidy, both auto- and allo-, is a fairly common mode of speciation in plants. As Allen Orr and I noted in our book Speciation (read chapter 9), roughly 2-4% of speciation events in flowering plants involved polyploidy of one sort or another, and maybe as many as 7% of speciation events in ferns. This is a rough estimate, and the real frequency could be higher. But polyploid speciation in animals is much rarer, and I won’t go into the suggested reasons for it (see pp. 333-337).

There’s another form of hybrid speciation called “homoploid hybrid speciation” or “recombinational speciation.” In that process, a hybrid is formed between two species, and then, if it is at least partly fertile, the genes from the different parental species can sort themselves out into new combinations of genes or chromosome arrangements from the parental species. If the new sorted-out population is reproductively isolated from the two parental species that produced it, we have a new homoploid hybrid species.

Many biologists (I won’t name them) have posited that this kind of speciation is rampant in nature, so that it’s not just the occasional sneaking of genes between species that’s important, but also the wholesale formation of new species after hybrid formation. Lots of suggested examples of such species have been given.

However, it appears that most of the evidence for non-polyploid hybrid speciation is weak. That, at least, is the conclusion of Molly Schumer, Gil Rosenthal, and Peter Andolfatto in a 2014 paper in Evolution (link and free access below), a paper that I only learned about at CoyneFest. Schumer et al. argue that good evidence for a non-polyploid hybrid speciation event requires satisfying three conditions, and I quote:

To demonstrate that hybrid speciation has occurred given this definition, three criteria must be satisfied: (1) reproductive isolation of hybrid lineages from the parental species, (2) evidence of hybridization in the genome, and (3) evidence that this reproductive isolation is a consequence of hybridization. By contrast, a large number of empirical studies have simply used genetic evidence of hybridization (Criterion 2) as support for hybrid speciation. . .

The authors argue that there are many ways that a species can look as if it’s a hybrid without actually being the result of full-scale hybridization (or any hybridization); that in some cases a hybrid lineage hasn’t been tested to show that it’s interfertile with other members of that lineage and reproductively isolated from the parental species, and, especially, there are almost no demonstrations that the genes or chromosome arrangements of parental species have sorted themselves out in a way that has created a reproductively isolated homoploid hybrid. That is, few people have shown that the reproductive isolation of a putative hybrid species involves genes that came from the parental species rather than, say, genes that evolved via natural selection after hybridization.

You can read the paper for details, but Schumer et al. conclude that despite the big noise from some biologists, there are only four cases of homoploid hybrid speciation that meet their criteria. Three of them are in one genus: the wild sunflower Helianthus, which has formed three diploid species—all adapted to novel environments—by hybridization of pre-existing species and the sorting out of chromosome arrangements that, with their divergent genes, reproductively isolate the hybrid population from the parents. That superb work was done by Loren Rieseberg and his colleagues.

The other case is the butterfly Heliconius heurippa, which genetic evidence shows almost certainly resulted from hybridization between the species Heliconius cydno and Heliconius melpomene, H. heurippa has a hybrid wing pattern, which you can see below, and it’s been shown that each species, as well the “hybrid”, are reproductively isolated from the others because males mate almost entirely with females who have their own wing patterns. Thus H. heurippa (shown below with its parents) satisfies all three of the authors’ criteria, for the genes causing reproductive isolation are precisely the color-pattern genes derived from the two parental species.

2013-03_naturkundemuseum_berlin_heliconicus_heurippa_anagoria

H. heurippa (the hybrid species)

heliconiusmelpomene

H. melpomene

heliconius_cydno

H. cydno

The upshot is that while the movement of individual genes between both plant and animal species is more common than evolutionists assumed before the gene-sequencing era, there is still scant evidence that entire new species of animals form via hybridization. Hybrid speciation is more common in plants, but only through the unusual mechanism of polyploidy, and homopoloid hybrid speciation (without an increase in chromosome number) doesn’t appear common in either plants or animals.

________

Schumer, M., G. G. Rosenthal, and P. Andolfatto. 2014. How common is homoploid hybrid speciation? Evolution 68:1553-1560.


02 Oct 09:49

A Guide to Invertebrate Zoology on Twitter!!

by ChrisM
Aletia03

For all Marine animal lovers and twitter users out there, here's a fantastic list of people and organizations to follow !

Marine invertebrates potpourri
image by the indubitable Arthur Anker
This week. Something a little different. I was doing a short presentation for some colleagues about using social media next week and I began accumulating Invertebrate Zoology accounts on Twitter... which at one time were quite rare and realized that it would be a good thing to share all of them.

It surprised me that SO MANY have since become established. I remember many years ago when it was less than 6 people and most of it was secondary to blogging!
Now, not ONLY are there many, MANY IZ Twitter themed accounts specializing on specific taxa, there are actually REGULAR twitter events...

Invertebrate Themed Twitter Events

Weekly..

#TrilobiteTuesdays. Held every Tuesday.  If you are into Paleozoic arthropods then Tuesdays are YOUR thing!

#WormWednesday: Held every Wednesday. These bring forth all manner of worm-like phyla: Polychaeta, Annelida, Nematoda, Platyhelminthes, Acoela, and so on and so forth..

#SpongeThursday: Held every Thursday. Love the Porifera? the Hexactinellida? Go forth and
enjoy/post about them!

Honorable mention goes to #FossilFriday which is mostly about Dinosaurs and vertebrates..but you get some ammonites and other invertebrates in there pretty regularly...

Yearly..
#CephalopodAwarenessWeek. aka #CephalopodAwarenessDays Every year from October 8 to 12.  You can keep on updates at @cephalopodday. Basically 5 days celebrating EACH class of cephalopods and then some...
  • October 8 – Octopus Day, for all the eight-armed species
  • October 9 – Nautilus Night, a time for all the lesser-known extant cephalopods
  • October 10 – Squid Day/Cuttlefish Day, or Squidturday, covering the tentacular species
  • October 11 – Myths and Legends Day, for all the fantastical cephalopods of movies, literature and legend. 
  • October 12 – Fossil Day
#Polychaete Day. Held yearly on July 1 ever year. (Older hashtag was #InternationalpolychaeteDay).  In conjunction with polychaete related events at the NMNH and other museums.   This day honors international polychaete worm expert Dr. Kristian Fauchald on his birthday July 1st. Celebrates all manner of polychaete (and related) topics!  Here were my posts from 2015 and 2016. 

#SeaSlugDay. Held every year on October 29th in honor of Dr. Terry Gosliner's birthday! Celebrate by posting images, videos and links to all manner of shell-less marine gastropods! Nudibranchs and their kin! My post from last year. 

And of course #Okeanos when the NOAA vessel Okeanos Explorer goes into research/streaming mode!  in which case, there are new deep-sea invertebrate posts for several hours every day for about 2 to 3 weeks!!

Various Twitter accounts/Persons with Invertebrate themed content
from the USNM Invertebrate Zoology FB page @InvertebratesDC
So, here we go. All said and done a list of about 65 IZ twitter accoutns! A list of all the accounts I could locate which focused primarily on Invertebrates, exclusive of insects and arachnids.  Yes, sorry land-based arthropods but you are a whole thing all on your own.

This will be a fairly subjective list-I focused mainly on marine groups and those with academic or otherwise focused content that I thought was appropriate. Activity was also a consideration. Some accounts looked essentially inactive and were not included.

Let me clear that there are a LOT of accounts which have a broader focus that regularly include Invertebrate Zoology themed tweets, including aquariums, natural history museums, etc. and frankly those have so many followers its unnecessary to give them much more publicity anyway..

There were MANY, many individual accounts of photographers, naturalists, educators, scientists, etc. who for one reason or another I just couldn't include for the sake of space, focus, etc.

And there are some topics, for example about coral reefs, there's a TON of coral-related accounts and I simply could not list them all... A search on Twitter's search engine will get you all of those names pretty quickly though.

So, please don't take an omission as an offense. In fact, if you've got an IZ twitter account that you'd like me to know about, please let me know and if I think its appropriate, I'd be happy to include it.

As a side note: my search for these Twitter accounts took me to some interesting places and its curious to see how many of of the phylum or other taxonomic names have made it into popular use: band names, student groups, social clubs, business organizations, video games, so on and so forth...

General Accounts:
Invertebrate Zoology department of the NMNH at the Smithsonian @InvertebratesDC The official account for one of the most active Invertebrate Zoology departments in the world.

Heidi Gartner. @RBCMInverts. Collection Manager at the Royal British Columbia Museum Invertebrate Zoology dept.

Annelida & Segemented Worms

Dr. Christoph Bleidorn @C_Blei. Evolutionary biologist at the MNCN in Madrid

Dr. Conrad Helm. @conrad_helm. Sars International Center at the University of Bergen. Works on the systematics of segmented worms.

Brachiopoda
Brachiopod research at the Natural History Museum in London @NHM_Brachiopoda.

Bryozoa
Bryozoan research at the Natural History Museum in London @BryozoanNHM This is, I daresay, the finest Twitter account about bryozoans I have seen to date!!  Both fossil and living!

Cnidaria
Dr. Allen Collins, NMFS/Invertebrate Zoology NMNH. @tesserazoa. Specialist in jellyfish systematics, sponges and metazoans relationships.

Australian Coral Reef Society. @AustCoralReefs. Official twitter account of the Australian Coral Reef Society.

Dr. Casey Dunn, Brown University. @caseywdunn. Evolutionary biologist at Brown with a special eye towards siphonophores! He also produces Creature Cast videos.

Dr. Cheryl Lewis Ames,  @boxjellytalkNMNH/University of Maryland, box jelly expert.

Coral Morphologic. @CoralMorph. Strong visuals, images, videos of cnidarians and many other invertebrates.

Gates Lab @GatesCoralLab. Coral Research at the Hawaii Institute of Marine Biology.

Dr. David Plachetzki. University of New Hampshire. @plachetzki.  Cnidarian genomics.

Dr. Mercer R. Brugler @ProfBrugler. Professor at City Tech, SUNY, Taxonomy & Systematics of Black Corals & Anemones.

Medusozoa Columbia. @Medusozoacol.  Jellyfishes of Columbia!

NOAA Coral Program @NOAACoral.  Official Twitter account for the NOAA Coral Reef Conservation Program.

Dr. Rebecca Helm. @RebeccaRHelm. Woods Hole Oceanographic Instition.  Jellyfishes and all manner of swimming cnidarian.

Dr. Paulyn Cartwright @pcart. Professor at the University of Kansas specializing in Cnidarian Evolution.

Dr. Andrea Quattrini. @quattrinia.  Harvey Mudd College. Studies deep-sea corals.

Crustacea
Miranda Lowe, @NatHistGirl. Principal curator of Marine Invertebrates at the Natural History Museum in London.

Dr. Tammy Horton, Amphipod taxonomist at the Discovery Collections in Southampton @tammy_horton. 

Adam Hadsall. @_Nezumiiro_  Tweets #craboftheday and many other items of carcinological interest!

Echinodermata
Chris Mah, Research Associate at the NMNH. @echinoblog. I work on sea stars but know stuff about things.

David Clark. @Clarkeocrinus. A great account for enjoying Paleozoic and fossil stalked crinoids!

Fossil Worms (Miscellaneous)
Luke Perry. At the University of Bristol in the UK/Natural History Museum. @Cambriannelids. Works on Cambrian worms, primarily annelids.

Hemichordates, deuterostomes, etc.

Dr. Chris Cameron. @InvertEvo at the University of Montreal. One of my colleagues who studies the evolution and development of deuterostomes, especially hemichordates.

Invertebrate Paleontology

Dr. Dave Rudkin, @RudkinDave. Royal Ontario Museum. Studies Paleozoic arthropods and other fossil invertebrates.

Invertebrate Vision
Dr. Michael Bok at the University of Hawaii @mikebok. Studies Vision in invertebrates.

Leeches (Hirudinea)
Dr. Anna Phillips, Curator of leeches and parasitic worms at the NMNH, Smithsonian. @Annalida500.

Dr. Mark Siddall Curator at the American Museum of Natural History. @theleechguy. 

Dr. Sebastian Kvist, Curator at the Royal Ontario Museum. @sebastian_kvist. Annelid & leech systematics.

Mollusks-Bivalves
Dr. David Hayes. @Gnarly_Larvae at Eastern Kentucky University. Works primarily on molecular ecology and freshwater mussels.

Freshwater Mussels. @WeNeedMussels. What more can you ask for? A Twitter account entirely devoted to Freshwater mussels!

Mollusks-Cephalopods
ALCES: The AUT Lab for Cephalopod Ecology and Systematics. @ALESonline.  Devoted to studying cephalopod biology, especially deep-sea squids

Research account for fossil cephalopods at the Natural History Museum in London. @NHM_cephalopoda

CIAC-The Cephalopod International Advisory Council. @cephCIAC. The Cephalopod International Advisory Council is a scientific group for cephalopod researchers worldwide

Dr. Louise Allock. @DrShmoo at the National University of Ireland, Galway. Deep-sea octopuses!

The Octopus Newsletter Online (TONMO) @cephs  A hub for cephalopod research and interest.

Dr. Stephanie Bush, Monterey Bay Aquarium. @podlett. Deep-sea Octopus biologist/systematist at MBA.

Mollusks-Gastropoda (shelled snails & slugs)
Dr. Chong Chen, Biologist at JAMSTEC who works on deep-sea snails @squamiferum.  

Jessica Goodheart. @sluglife28. PhD student at the University of Maryland/NMNH. Studies sea slug systematics and behavior.

Dr. Kevin Kokot, @kmkocot. University of Alabama. Mollusk & metazoan phylogeny.

Nematode Worms
The Blaxter Lab (Dr. Mark Blaxter, University of Edinburgh),@blaxterlab.  Nematode, tardigrade and other invertebrate genomics/genetics.

Nemerteans (Ribbon Worms)
Dr. Jon Norenburg, dept. chair of the Invertebrate Zoology dept. at the NMNH. @Jnorenburg and @nemertinator (personal account)  Specializes in ribbon worms and meiofauna.

Iberian Nemerteans. @nemertan. Truth in advertising. A Twitter account about ribbon worms based in Spain.

Parasites (broadly)
Twitter account for the American Society of Parasitologists @AmSocParasit All parasites. All the time.

Tommy Leung, Parasitologist who authors the "Parasite of the Day" blog. @The_Episiarch

Pelagic Invertebrates
Leann Biancani, @LeannMBiancani PhD student at the University of Maryland and the NMNH. Studies the biology and relationships among pelagic invertebrates, including amphipods and polychaetes.

Dr. Steve Haddock, MBARI. @beroe Dr. Haddock is an expert in ALL manner of pelagic deep-sea invertebrates.

Plankton
Dr. Richard Kirby, based in Plymouth, United Kingdom. @planktonpundit. A wonderful account with regular images and videos of planktonic/nektonic and other related organisms.

Platyhelminthes & Flatworms
Dr. Ulf Jondelius @ulfjo, specializes in aceolomorph "flatworms" at the Swedish Museum of Natural History.

Dr. Jean-Lou Justine, specialist on free-living land flatworms at the MNHN in Paris. @Plathelminthe4 If you are REALLY into Bipalium and other terrestrial, free living flatworms this feed is for you!

Polychaete Worms
UPDATE: Christoph Bliedorn has produced a magnificent list of Tweeting Polychaetologists here: https://bembecinus.wordpress.com/2016/10/05/a-list-of-tweeting-polychaetologists/

The Polychaeta Database @WpolyDB Twitter account of the World Polychaete Database (WoRMS)

ケムシ屋 @alciopidae. I don't have a full name unfortunately.  A Japanese polychaete taxonomist (Cirratuliformia/Alvinellidae/ Myzostomida/Opheliidae/Polynoidae etc...)

Dr. Helena Wiklund. @helena_wiklund, University of Gothenberg, Germany. Polychaetes and annelid diversity.

Maddie Brasier. @Madsbrasier.  Studying Antarctic polychaetes.

Dr. Shinri Tomioka. @Capitellico PhD student at Hokkaido University in Japan studying polychaetes.

Dr. Torkild Bakken. @TorkildBakken. Marine biologist at NTNU University Museum, polychaetes and other deep-sea diversity.

Porifera (the sponges)
Twitter account for deep-seasponges.org @Deepsea_sponges You don't get much more specific than this, where deep-sea Porifera are concerned!

Dr. Jackson Chu @jwfchu. Glass sponges and benthic ecology.

The Pawlik Lab @PawlikLab at the University of North Carolina, Wilmington. Sponge chemical ecology and biology.

Dr. Ana Riesgo at the Natural History Museum in London. @anariesgogil  Sponge researcher at the British Museum.

Dr. Bob Thacker at Stony Brook University. @thackerbob 
Ecology and systematics of sponges,  Involved with the Porifera Tree of Life Project.

Protists!
The International Society of Protistologists! @protistologists . Pretty much all in the title.

Psi Wavefunction.@PsiWavefunction. Protist blogger and scientist.

Tardigrades
Dr. Daiki Horikawa. University of Tokyo. @daikidhori  Tardigrade biology & genomics!

19 Jul 22:09

Consumers should seek a variety of fiber sources to get the maximum health benefits

Consumers who get fiber from many sources -- both naturally occurring and added in manufacturing -- may benefit more than people who limit their intake to a single type, according to an expert.
12 May 09:39

cynique: popculturebrain: Leading Men Age, Leading Women...

by cute-gurls-club
Courtney shared this story from The Babe Brigade:
Good concept, lousy data viz.









cynique:

popculturebrain:

Leading Men Age, Leading Women Don’t | Vulture

There are more charts if you click through.

I’m so glad this info graphic is going around, because so many people don’t realize how ageism and misogyny play hand in hand and how the sexualization of young girls play into this.

25 Nov 08:26

Our god vs. theirs

by whyevolutionistrue

A New Yorker cartoon tw**ted by Massimo Pigliucci. Remind you of a certain Monty Python skit?

Screen Shot 2014-11-24 at 12.31.53 PM


13 Nov 08:20

(More than!) Five Cool Things We Could See if the Okeanos Went Back to Indonesia

by ChrisM

So, over the weekend, the livestream of Okeanos Explorer briefly mentioned and entertained the idea that they might head back to Indonesia for a revisitation of their inaugural expedition from 2010! (The INDEX-SATAL Mission). (I think someone mentioned the ambassador was on ship?)

That expedition was, of course, 4 years ago and the program had just begun. Updates were not as forthcoming. But an opportunity to RETURN to Indonesia? With the benefit of hindsight, experience and further preparation?? That would be awesome!

That area is known as home to probably one of the MOST diverse marine faunas of anywhere in the world.  And although there's a lot known from shallow and deep habitats, the deep sea areas (below 200 m) in the Indonesian area will likely make all the stuff R/V Okeanos Explorer and E/V Nautilus have been observing in the Atlantic look like a goldfish bowl by comparison! 

A LOT of the species in this area are likely undescribed. A veritable gold mine of biodiversity to be studied! Some of these taxa have no Atlantic members. (It would be even better if these were enhanced by collections of course!)

Here's some highlights that I would love to see again!  

1. The Sea Cucumbers
I don't think I've seen ALL the pics but the ones I have were brilliant. This red elasiopod would be something I think everyone should see again... 
Okeanos from expl2168

The oddball swimming sea cucumber with the big lobe: the appropriately named Psychropotes
From Okeanos expl5494
and this gorgeous swimming Enypniastes? Or something similar to it.. But wow! Transparent body! You can literally SEE the sediment filled intestine THROUGH the body wall!
from Okeanos expl5475
2. The Hydrothermal Vents
When people talk about hydrothermal vents, there's 2 or 3 places that register as the most iconic spots.. the Mid-Atlantic and the East Pacific Rise.  There's others but one vent site that no one really talks about much?  The ones surveyed by Okeanos in Indonesia! 

These are the hydrothermal vents found on the undersea volcano Kawio Barat (West Kawio) 
from Okeanos expl2184
Amazingly gorgeous spires created by hydrothermal activity. 0.5 to 1 meter tall active and inactive spires on the summit of the Kawio Barat submarine volcano. Spires observed at 1849 meters depth. 
From Okeanos expl2188
Further venting through some of these chimneys gives us these amazing structures covered by barnacles! 
from Okeanos expl 2195
What's that? you want to see those barnacles more close up? here ya' go...
fr. Okeanos expl 2196

3. The Insane Stalked Crinoid Diversity
One of the very interesting animals noted in the expedition pictures notes was the incredible diversity of stalked crinoids which were observed.. I've only shown two of them below..but the gallery shows many different types of stalked crinoids.. to say nothing of the feather stars (aka unstalked crinoids)

This red one, as identified by Dr. Marc Eleaume in Paris is likely Proisocrinus ruberrimus 
From Okeanos expl5403
 And an likely unidentified member of the Hyocrinidae...                                     
                            

4. Bizarre and wonderous Deep Sea Sponges (Hexactinellid or Glass Sponges? I think)
A wonderous cladorhizid carnivorous sponge from about 1000 m! 
from Okeanos expl5560
A bizarre sponge with unusual body morphology
from Okeanos expl 5599
5. And the underappreciated Slit Shell Snails (Pleurotamariidae)! 
I'm honestly not sure how many people recognized a majority of the animals observed on the 2010 dive but some of the shots from the NOAA Photo Library showed some awesome images of that most treasured of marine snails: The Slit Shelled Snail (family Pleurotamariidae).       

These snails have always held a certain appeal to shell collectors. The shells are known from the fossil record and have a distinct slotted opening near the shell's opening. They are one of the largest marine snails observed in deep-sea settings..
from Okeanos expl5650
 The images place the slit-shell moving into this gorgeous field of corals..                                  
From Okeanos expl 5648
Some of these snails are predators on echinoderms, such as sea stars and possibly serpent stars (ophiuroids). So, conceivably this one is about to feed...
From Okeanos expl5646
PLUS! those Hermit Crabs with shells replaced by sea 
anemones! 
fr. Okeanos 5671
fr. Okeanos 5672
ONE More GREAT thing?? In situ observations of WOOD FALL COMMUNITIES!  These are some of the weirdest, rarest of deep-sea habitats as written by Craig McClain at Deep-sea news as he's documented here and here.  What are they? Deep-sea communities based entirely on wood from the surface that have fallen to the deeps!!

Some of these species are known ONLY from wood substrates!

But how often do you get to see an established wood fall community??  Here's what looks like those wood-eating urchins I wrote about a few years ago...
Okeanos expl 5968
and here's a close up of some more urchins and polychaetes
from Okeanos expl 5972

and yeah, there was a LOT more...

So, Okeanos Decision Committee?? LET'S GO BACK TO INDONESIA!!! 
19 Feb 20:08

Photo





















19 Feb 20:08

scienceyoucanlove: Silent but Deadly by Richard Wheeler,...

by ushishir


scienceyoucanlove:

Silent but Deadly

by Richard Wheeler, University of Oxford

A stylized representation of Trypanosoma brucei, which causes African sleeping sickness in humans and nagana in cattle, is shown in the bloodstream.

Image: 3D rendered image created in Blender based on scanning and transmission electron micrographs.

through Cell

19 Feb 20:08

Dream Girls of Ikenaga Yasunari   [池永康晟], (1965,Japan) Using...





















Dream Girls of Ikenaga Yasunari   [池永康晟], (1965,Japan)

Using the simplicity of indian ink and linen canvas Ikenaga Yasunari has captured a simple serenity in the the faces of his female portraits.This calm sensuality is highlighted by the richness of their surroundings. Yasunari’s Japanese heritage has inspired a style of painting which is characteristic in his work. This ancient technique of Nihonga is a traditional Japanese artform using a Menso brush and ink. With this Yasunari has successfully captured an essence of the past with a pallet of muted tones , but  has injecting a modern twist to each piece with his use of pattern and cloth.

19 Feb 20:08

Alexandra Khitrova

19 Feb 20:07

The many shades of twilight by photographer Alex Noriega





















The many shades of twilight by photographer Alex Noriega

04 Oct 15:50

azertip: Peleng art