So, uh, I just learned that this is what a pufferfish skeleton looks like, and I think you all should know too pic.twitter.com/ecCXN8RTAV

— Liz Weinberg (@eaweinberg) November 30, 2018

So what are you looking at other than some truly sweet evolution?

What you are looking at are the spines of pufferfish composed of nanocrystalline hydroxyapatite,  protein(collagen),  and water, the same materials as scales.  Indeed, these spines are just modified scales.  And like other scales, these spines originate during development from the mesoderm layer of the dermis or the skin.

Dr. Brian Sidlauskas, Associate Professor and Curator of Fishes at Oregon State University,  notes puffers evolved from a group of fish (Porcupines, Molids, Triggerfishes, and filefishs) that all possessed ctenoid scales, denoted by small teeth along their outer edges.  “Filefishes actually feel fuzzy.  So it isn’t perhaps too surprising to imagine those scales expanding and getting more and more spiny.”

As you might expect, these spines evolved as anti-predator defense, similar to the ability of puffers to inflate.  However, it looks like the inflation likely evolved before the spikiness.

Evolution is amazing.

The post You Should Definitely Know about Pufferfish Skeletons first appeared on Deep Sea News.

Mola Mola – the Pandas of the ocean? You Decide!

(Note the below post contains possibly NSFW language – copious amounts of swearing.)

The post Ocean Sunfish are the most useless animal (an epic rant) first appeared on Deep Sea News.

*alternative titles include “Looking a gift seahorse (genome) in the mouth”, “My kingdom for a seahorse genome”, “Hold your seahorses“, and “The galloping evolution of seahorses“.

Let’s face it, seahorses, pipefishes, and seadragons are messed up. That’s not a subjective opinion but an evolutionary fact.  It’s like all the approximately 300 species in Syngnathidae (the family of fish that contains all these critters) held a meeting and decided unanimously “Nah, screw it, we’ll do things however we damn well please.”  The Syngnathids are revolutionaries of the fish world.  ¡Viva la Evolución Revolución!

Seriously, almost everything in these species is different.  There is the elongated snouts and small mouths and jaws.  The pelvic and caudal fins are often gone.  The scales are replaced with an armor of bony plates.  Let’s not forget about the whole “male pregnancy” thing where the males nourish the developing embryos in a pouch.  Seahorses take it all to a whole other level with the prehensile tail and the vertical body axis.

So ultimately, one is left wondering what’s up with those genes?  Well, thanks to an intrepid group of geneticist, the complete genome of the tiger tail seahorse, Hippocampus comes, is complete.  With the full genome comes great power, the ability to compare this genome to the other sequenced fish.

Part of the story regarding the bizarreness of seahorses is gene loss.   Secretory calcium-binding phosphoprotein (SCPP) genes code for matrix proteins that are important in the formation of bone and teeth.  These genes are completely missing in Hippocampus comes and may explain why seahorses do not have teeth.  Did I forget to mention that?  Yeah seahorses and seadragons are toothless. The tbx4 gene, conserved in jawed vertebrates, acts as a regulator of hindlimb formation.  The gene is completely absent in the seahorse genome and explains the absence of those pesky pelvic fins.

What about that whole “male pregnancy” thing?   The H. comes genome contains six pastn genes, part of a family of genes that regulate the hatching of embryos.  The researchers conducted extra work, like the genome was not enough, suggesting a role for these pastn genes in brood pouch development and/or hatching of embryos within the brood pouch prior to birth.

Seahorses have also apparently lost many conserved noncoding genes (CNEs) that function as enhancers, repressors, and insulators of other genes.  1,612 CNEs have been lost in seahorses.  Compare this to the 281 in the Nile perch.  It is unclear how the loss of the CNEs may be related to some of the oddities of the seahorse, but loss of CNEs is tied to moderate short stature and shortened limbs in humans.

How I imagine the scientists of the study acted once they finished the genome

The awesomeness of this kind of work cannot even be articulated.  The researchers have done an amazing job of unpacking the genome of a seahorse and showing how genome evolution directly leads to all the uniqueness of seahorses.  Admittedly, I am little disappointed in not seeing a discussion of the prehensile tails genes and armored plating discussed. I guess I’ll need to wait a bit to build my army of aquatic minions to take over the world.

The post In the evolution of fishes, this is a one seahorse race* first appeared on Deep Sea News.

I am on a ship 950 miles away from the nearest landmass. Here, in the middle of the equatorial Pacific Ocean, our team sends a remotely-operated vehicle 2.5 miles down to the flat abyssal plain. As deep-sea biologists, we get to see some pretty AH-MAZING sights and this time is no exception: an anemone-like animal with 8-foot tentacles that billow across the seafloor. This creature, Relicanthus sp., is so different from other anemones it was recently moved to a new order.

As incredible as seeing this tentacled beast was, I couldn’t help but feel a tinge of sadness. It’s difficult for a marine biologist working in an area that may be forever changed within the next two decades. As the demand for metals increases, humans are seeking resources in ever more remote places and the next frontier of mining will likely take place in the deep ocean.

So what are countries after 3 miles deep in the central Pacific Ocean? Potato-sized lumps of metallic ore laden with cobalt, copper, nickel and other rare metals known as polymetallic nodules. The Clarion-Clipperton Zone has the most valuable beds of these nodules that sit like cobbles on a street and form at a rate of a few millimeters per million years. As the Clarion-Clipperton Zone is in international waters, it falls under the mandate of the International Seabed Authority (ISA). So far, there have been 15 mining exploration areas allocated, each up to 75,000 km² or roughly the size of Panama.

Let’s be honest, nodule mining is going to do some damage. Nodules will be removed resulting in local extinctions of the many animals (corals, sponges, bryozoans, polychaetes, nematodes etc.) that call these nodules home and leaving no possibility for their re-establishment in the future. Machines, similar to combine harvesters, will disturb and compact large swathes of sediment, kicking up sediment plumes, which will travel for kilometers before depositing elsewhere. Further entombment of the seafloor will occur when tailings are discharged into the water column. Not to mention other possible impacts that include light and noise pollution from machinery, and major changes to the geochemistry of the sediment, food webs and carbon sequestration pathways. The cumulative impacts of these operations aren’t yet understood but will likely be long-standing and ocean-wide.

Despite this looming threat, the Clarion-Clipperton Zone is critically underexplored. We know little of what species live there. It is mandatory that contractors undertake baseline studies of the biology living at the seafloor before EIAs and mining can begin. The ABYSSLINE Project, which I work on, is doing just that in the easternmost claim area leased to UK Seabed Resources Ltd (UKSRL). My research is trying to find out what megafauna (the awesome charismatic animals over 2 cm in size) live in the UKSRL claim, how abundant and diverse they are, and what ranges they occupy, not only within the claim but also across the entire Clarion-Clipperton Zone. Over the last two years, ABYSSLINE scientists have spent over two months out in the middle of the Pacific Ocean sampling the seafloor with a menagerie of oceanographic equipment (plankton pumps, fish traps, a remotely-operated vehicle, an autonomous underwater vehicles, sleds, corers etc.).

Preliminary results show that the UKSRL claim area is rich not only in metals but also in life. The seabed, at a first glance, appeared to not have much living there. Taking a closer look, we realized that there were small animals everywhere: tiny white corals, pink and purple sea cucumbers, bright red shrimp and strange unicellular animals that create sedimented homes the size of your fist. On our first expedition, we sampled an area the size of Hong Kong (30 x 30 km) and found 170 tentative species of megafauna and that’s likely an underestimate! These levels of biodiversity are the highest in the Clarion-Clipperton Zone and are comparable to many other abyssal regions worldwide. We also collected 12 megafauna species and half of those were new to science, including some of the most commonly seen, reiterating how little we know of the abyssal life in this region.

The post Megafauna and Minerals on the Pacific Abyss first appeared on Deep Sea News.

In the heat of the cold war when cloak-and-dagger espionage went below the sea, the US Navy was listening to fishes. Ideally, after identifying all the strange sounds generated naturally by a vast array of noisy marine creatures, the military might be able to parse out sounds made by Soviet subs and their underwater communications.  What these researchers found was that Jacques Cousteau’s “Silent World” wasn’t so silent at all, but was a clamorous crash of snaps, crackles, pops, grunts, squeaks, and pounding beats that sounded more like a Manhattan rush-hour than a sea of tranquility. Yes, fish can make sounds, but why isn’t their underwater chorus more like the melodic serenade of songbirds in a terrestrial woodland, especially since some fish are named after some of the most pleasant-sounding musical instruments?  In short, it’s false advertising.  Fish make lousy musicians, and the names we bestowed upon them was more about our shoddy interpretation of their instrument-like shape rather than their own orchestral virtuosity.  In an unexpected and elusive gift of spare time during a very short holiday, I employed my limited graphic skills to imagine what these musical fish might achieve if they actually lived up to their names, and the kinds of vintage vinyl LP albums we might find some day in the bin of a thrift store.  Don’t ask why, please just enjoy.

Black Drum
True to their name, this fish does generate a bongo beat from specialized muscles strumming their taught air bladder.  In fact, drums and croakers are some of the loudest percussionists in the fish world, often keeping up the tempo over long spans of time so that a placid Florida bay sounds more like a Burning Man drum circle.  Specific reasons for sound generation among the fishes in the Sciaenidae are not fully known, but ichthyologists suppose these mad beats are produced by the male black drum to attract a female, spending more effort and generating a higher level of sonic innovation than a hippie in that Burning Man drum circle, and likely with better results at attracting a female.

Trumpetfish
Few musical instruments convey the range of American jazz than the trumpet.  From the brassy blare of Louis Armstrong, to the swinginging stylings of Frank Sinatra’s backing Capitol Records Orchestra, to the mariachi pop of Herb Alpert & his Tijuana Brass.  Yet trumpetfish can generate none of this urgency nor excitement because it is silent, boring, and shy.  These elongate fishes look more like a dour reed flute slowly hovering through a shallow coral reef.  Having a narrow, tubular mouth like their related seahorses and pipefish cousins, they sneak up to smaller fishes and in an instant, suck them up that tube and into their belly without making a sound.

Cornetfish
Also a misnomer in the sense that they neither look nor sound like a cornet, and are often mistakenly called ‘clarinetfish’, these longer, lankier cousins of the trumpetfish also use their flute-like mouth to suck up unsuspecting fishes. A real cornet provides a mellower sound for smoother jazz, yet these fish produce no mellow nor smooth sounds to soothe the hurly-burly life of the reef.

Guitarfish
It would require a very inventive, and likely an exceedingly inebriated, person to make any musical sounds with a guitarfish.  These inshore rays of the genus Rhinobatos are found in tropical and temperate waters and only vaguely resemble the stringed instrument responsible for the sensual sounds of flamenco. Like virtually all sharks, rays, and skates, they have no ability to produce sound. But in the wide world between traditional classical guitar finger picking and heavy metal air guitar, a savvy performer may indeed be a spot for this fish after all.

Fiddler Ray
Following the apparent worldwide inability for fishermen to fully remember what stringed instruments really look like, these Australian rays only resemble the romantic violin if you squint your eyes and pour on the imagination. If you are Australian, forget the imagination and pour on another can of Cooper’s. What makes Trygonorrhina only slightly more realistic are the stripes that cris-cross their body, lending a bit of an optical stringed tangle in need of some serious tuning. If you are Australian, forget the tuning and pour on another can of Cooper’s.

Banjo Catfish
If there isn’t an Appalachian bluegrass performer named Banjo Catfish, there should darn well be. Instead, the actual banjo catfish is a relatively small member of the family Aspredidinae who live in muddy waters of the Amazon basin, camouflaged among waterlogged leaves and – no surprise – not looking much like a banjo. While many catfish species do grunt, croak, bubble and squeak, this silent silurid does none of that, nor even hums any of the Flat & Scruggs picking styles from Deliverance.

The post The Disappointing Reality of Musical Fish first appeared on Deep Sea News.

I take on a senseless internet meme and make it even more so – for science.

With the northern hemisphere days getting shorter, and the air getting crisper as autumn approaches, we reflect back on the summer soon passing. You may not have known, but this was the “Summer of the Goat” as christened by internet sites, and further blessed with countless video and photographic outpourings of humanity’s apparent love of goats. The cyber cuteosphere erupted with frolicking baby goats, bipedal goats, narcoleptic goats, goats with puppies, goats with British royalty, bleating goats singing along to the theme from Jurassic Park, and this was just the start. Though I certainly appreciate goats for their sublime comedic gestalt, that was certainly not my summer. As a marine biologist I had a very different summer – the Summer of the Goatfish.

Goatfishes are found worldwide in shallow, warm waters, and as an ichthyologist with pathetic swimming skills, I’ve dog-paddled alongside them the shallows of the Gulf of California, waded with them in the Red Sea, and snorkeled among schools of them in Hawaii. This year I enjoyed them again in the Caribbean waters off Belize and the Cayman Islands, continuing my excitement of underwater fish-watching and reinforcing my admiration for these fishes, and at 55 species, that’s plenty to love.

Colors and patterns seen in goatfish represent a broad range of hues and textures, made even more spectacular by the fact that they can change colors. Many species will assume different day and night, or active and resting colors (like your work clothes and jammies), a feature that initially confused early ichthyologists as to just how many of goatfish species there actually were. Foraging groups of goatfish may hijack a school of fish like snappers, changing their color to match that of the other fish and blending unnoticed by the goatfishes’ smaller prey or larger predators.

Showing virtually no resemblance to their horned, hoofed, and smellier terrestrial namesakes, the pair of whisker-like barbels goatfish have on their chin vaguely resembled the scraggly throat-beard goats have (where the term ‘goatee’ came from, obviously) led earlier fisherfolk to dub these critters ‘goatfish’. While the beard of a goat (or the goatee of a hipster) serves no practical purpose, these goatfish whiskers are filled with chemosensory receptors that allow them to taste around for buried food as they comically tickle the soft sediments with these finger-like extensions.

At the first sense of food, goatfish ram their mouth into the sand, gulp a package of silt & food, then pass the load through their gills where sand exits and larger delicious bits of seafood are gulped down. Some fish forage individually, while others form large schools that move like an army of minesweepers over the ocean bottom uncovering worms, crabs, shrimp, and other invertebrates. Even though they are truly bottom-feeders eating other scavengers, they are still listed as a Kosher fish.

Over the centuries goatfish have been harvested as food. Easily caught by hook or net from shore, they were, and in many areas, still are, a common mainstay of seaside cultures. Early Greeks saw eating a goatfish as a sign as being an epicurean elite, and these fish were popular among banquets of the Roman ruling class, with high bounties being paid for especially large specimens. Hawaiian islanders esteem this fish today, and in early times they raised certain species of goatfish in ponds to supply the ruling Ali’I. Goatfish are caught by the tens of millions today in largely unregulated fisheries, both commercially and recreationally, and little data exist on just how much are yanked from the sea. In the Australian state of New South Wales for example, between 20-30 metric tons are hauled in each year. That’s a lot of goatfish.  But for me the joy lies not in eating them, but in how they forage, with a serious look on their faces while comically wriggling their little goatfish beard in the sand for food. That’s just as adorable as any goat tromping through playground rides. Enjoy the videos below:

Related articles

• Spotlight on Goatfish

The post Summer of the Goatfish first appeared on Deep Sea News.

Aided by new technologies and teams of overworked graduate students and unpaid interns, and prodded by the dismal decline of these huge rays at the expense of alleged ‘traditional medicine’, marine researchers are rapidly making big discoveries into previously unknown areas of manta ray life history. Like many things in nature that seem counter-intuitive, the largest animals in the sea eat the smallest, and mantas, the largest of all rays, are filter-feeders that strain tiny marine organisms with a sieve-like set of spiky rakes in their gills. But they need to sieve a lot of sea water to get enough teensy bits of food energy to grow to their massive size (up to 20 feet across), and to gain enough fuel to make long-distance and even trans-oceanic migrations. But one sure-fire way to get the high-energy protein shake a growing manta needs is to slurp up the end-product of a reef-fish sex party.

Studying mantas at coral reefs in the South Pacific and Indian Oceans, teams of researchers found direct correlations between spawning events of surgeon fishes, tangs, and butterfly fishes, and the seemingly sudden appearance of mantas, emerging out of the depths like bat-shaped Roombas  to vacuum up future generations of reef fishes. As the spawning parties get together and mill about the reef edge, a half-dozen or more ripe and randy fish will suddenly make a dash toward the surface and simultaneously release their eggs and milt (fish semen). Fertilization takes place in the open water and the eggs, and later the larvae, float offshore, and with any luck & favorable currents the young fish will later return to join their parents on the reef, or populate other reefs miles away. But just as the fish squirt their faint milky gamete clouds, the mantas zoom in to inhale the eggs and sperm. Their gills can only strain the eggs, and the microscopic sperm cells pass through their gills. This coital caviar packs a major nutritional boost for the rays.

Observations of this Caligulan feeding activity has been seen and documented before, but emerging research suggests that mantas specifically focus on spawning fish, and don’t just take an opportunistic grab at any piscine orgy they happen to stumble upon. Spawning events on reefs are often related to tidal or lunar cycles, so Mantas may be able to predict when and where these spawning groups will occur, and likely plan their movements to exploit the breeding cycles of these fishes. Outside of the breeding season and during the evening when reef fishes are sacked out from a busy day of spawning, mantas have much less of a triple-X diet. Moving offshore and into deeper water, mantas feed on deep-sea plankton, diving over 1400 feet (430 meters) and filtering out the tiny mesopelagic organisms in the Deep Scattering Layer that rise from the depths as night falls.

The post Mantas to Reef Fishes: I Drink Your Miltshake first appeared on Deep Sea News.

The post TGIM – Pufferfish can sculpt, what’s your excuse? first appeared on Deep Sea News.

Have some of your own to add? Drop us a line below.

Sources: Wikimedia Commons, Ron McPeak, Judi333, Trine Galloway, East Bay Express, Shutterstock

The post Fishes of Instagram #throwbackthurday first appeared on Deep Sea News.

We’re still working out the kinks…and trust us, these new things can get pretty kinky (#TWSS). Bear with us as we build up our visual smorgasbord, and be sure to check out our initial smattering of pinboards:

• Invertebrate Love – All invertebrate pictures, all the time
• Giant Squid – This board needs no explanation
• Habitats of the Deep – Showcasing what the deep sea actually looks like; it ain’t all mud plains!
• Gadgets & Gear – Because “every now and then you just need to stare at some cold hard steel”
• Waves + Fluds = Physics, baby! – All the physical oceanography goodness you ever wanted
• Let’s get it on – Come on, what would DSN be without a Pinterest board on marine sex?
• Fish, sharks, and marine mammals – Well someone needs to grow a backbone around here.
• Marine research bucket list – A personal board for us Deeplings, to showcase our most wished-for research questions and field sites
• The ocean…from SPAAAACE! – Satellite images of the ocean are so awesome that they need their own board.
• Drink up me harties – A board about beer and other tipples we drink while blogging
• Conservation & Conversation – Upcoming events, breaking news, viral content

The post Announcing the DSN Pinterest empire! first appeared on Deep Sea News.