lobe finned fish

My “high fantasy” setting was essentially in a very Tolkien-like world, only the Mideavel battles and the infamous war with the Orcs a thing of the distant past. The world is in modern day with machines and computers. Magic, a sort of wave-particle radiation, permeates the Earth which much technology and organisms depend on (notable exception of humans…).

Humans were Homo Sapiens as we know them. The most populous of all sapient species which most forms of magic. like fibre, is unabsorbable and goes right though our bodies. 

Dwarves are our closest relatives, a light magic using decendant of Neanderthals and the Denisovan hominins. Ranging from 4′6″-5′4″, Dwarves ate a diet heavy in meat and tubers and often lived in underground cmplexes, tho many now use “human-style” architecture. Humans and Dwarves could interbreed easily and produce fertile young.

Halflings” were a critically endangered species descendent of Homo floresiensis who prefers to stay out of global politics. Originally of no “use” there has been a boom of “interest” in them from Humans and Dwarves due to their possible connection with their mysterious extinct “progenitors” (Homo erectus)

Elves were high magic using decendants of Ardipithecus. Extremely lithe and vaguely gibbon-like, their high intelligence and extended lifespan of the elves is due to their heavy dependance on magic. Like the relation of Humans and Dwarves and Hobbits, Elves are actually a genus consisting of several species, notibly the High elves, Drow, and Wood elves (as humans call them). Elves were resistant to use modern technology and in general the tech of other people, older elves are still more likely to use cervine as transport then own a car, tho the hip younger generation of Elves take far more interest in other species.

Orcs were a sapient offshoot of Australopithicus. While often portrayed to be 8 foot tall, in life Male Orcs are only a bit larger then the average man (tho considerably stronger). Orcs hate how the Human-Orc conflicts are taught  and treated, wars that had a incredibly diminishing impact on their people and ended up driving them to poverty for decades.

Trolls had no relation to other species, instead being a mysterious race of sapient terrestrial echidnoderms. Going though highly complex life cycles, Troll larva start off as mouse size bilaterally symmetrical creatures, to the squat “lopsideders” and eventually becoming their 8 foot tall sexually mature adult form. Trolls are nocturnal, and make a thick mucus “cast” around their bodies when they rest that hardens during the day.

The “High Ones” are somewhat the equivalent to the Maiar, mysterious highly powerful entities seemingly like no other creature on earth. They mostly live in the Arctic (and Antarctic) circle, and have. They have curiosity in other species (and manipulating them), but are secretive of their own lives and tech, killing those who come near their settlements. (They also may or may not of been aliens…)

Ogres existed as a Homo habilis-like species that are raw meat and had the intelligence of dolphins. Dragons are semi terrestrial lobe finned fish that like elves were also highly dependant on Magic.

FROM THE OCEANS TO THE LAND

For millions of years life thrived in the abyssal plains and shallow seas, yet during this time the continental surface was barren and bleak, except for the few pioneering plants slowly creeping their way onto the land. As plant life got a foothold on the deserted surface rocks they began to transform the landscape waiting for animal life to follow. 

The transition from fish to tetrapod is one of the most important events in life’s history and we are lucky enough to have most of the puzzle on how it happened complete…

Eusthenopteron…
Eusthenopteron was a late member of a now extinct group of lobe-finned fishes and it existed during the Late Devonian, around 385 million years ago. The fishes pectoral and pelvic fins had a fleshy anterior part and very robust bones, the fore-fins exhibit a distinct radius, humerus and ulna and the pectoral fins have a femur, tibia and fibula showing that this 6 foot long fish was well on the way to developing primitive legs.

Pandericthys…
This was another lobe-finned fish from the late Devonian (378 million years ago). Panderichtys begins to show a more developed, longer humerus as well as primitive digits. Its tail is also more like the early tetrapod tails than the caudal fins of other lobe-finned fishes. They have also lost their intracranial joint to their skull (but it is still present), rather than it being external to the skull like in other lobe-finned fishes.

Tiktaalik…
Tiktaalik existed 375 million years ago and is still considered to be a lobe-finned fish although it shows even more tetrapod-like features than Panderichthys. The fleshy fins have primitive wrist bones and digits. They also have spiracles on top of their skull which may be possible indicators of primitive lungs. The humeral bones have large muscle scars suggesting that these appendages were highly mobile and the joints were capable of rotation, enabling Tiktaalik to have some sort of propulsion through the water. The eyes of Tiktaalik has moved further on top of a flatter skull and so it likely lived in a swampy, shallow water environment but was not yet completely terrestrial.

Acanthostega…
Acanthostega existed 365 million years ago and is the first to have distinct limbs, each of which has digits. However, the front legs were unable to bend forwards at the elbow and so it is unlikely that the animal was terrestrial as it was unable to move itself into weight-bearing positions.

Icthyostega…

Icthyostega was likely the first true tetrapod and existed between 365 and 360 million years ago. It has 4 robust limbs (with an unknown number of digits) and lungs which were still used in conjunction with gills. Icthyostega had wide overlapping ribs which likely helped to protect the lungs under its own weight without the buoyancy of water. Icthyostega has powerful limbs enabling it to haul itself onto the land but would still have spent much of its time in shallow, swampy water.

Creature Anatomy - Week 2

This is some of the work I did for the second week of the creature anatomy course I’m taking. Week two was focused on fish, amphibian and reptile anatomy.

I didn’t really have a strong idea for the creature I wanted to design initially so I started to research and explore the animal groups with the hope that during my studying something would spark an Idea.  I focused my attention on fish anatomy first since it’s the area I had the least experience with.  I did my first studies on a few extant species that I could easily find reference for.  I also kept my eye out for anything that caught my attention and might make a good base for a creature.  The goliath tiger fish was one of these.  I really love the big teeth and the sharply curved fins. 

I also did a couple pages of extinct species.  Here are a some studies featuring the ancient lobe finned fish eusthenopteron and and early amphibian capitosaurus. 

After doing a bunch of studies I did finally settle on an idea for my creature and began another round of sketches this time focusing specifically on those species I wanted to incorporate into my design.

I wanted the final creature design to incorporate elements form all three animal groups.  I also wanted to push the story telling in the design, so I spent some time writing a brief natural history for the creature.  I wanted it to be like something you might see in a field guide, just a quick summary explaining a bit about the world it comes from and some details regarding its behavior.  I wish I had time to get a color version and some additional studies of the creature finished. If I can I want to revisit it sometime in the future to flesh things out even more.

anonymous asked:

Do you make any other fish?

Here is a list of all fish I make currently, in no particular order:

Actinopterygii - Ray finned fish

Siluriformes
Corydoras pygmaeus
Corydoras sterbai
Corydoras aeneus
Otocinclus
sp.

Perciformes
Betta splendens
-Cichlids (coming soon)
Mikrogeophagus ramirezi
Cichlasoma festae
Cynotilapia afra
Pseudotropheus saulosi
Thorichthys meeki
Geophagus
sp.

Polypteriformes (coming soon)
Polypterus palmas

Sarcopterygii - Lobe Finned Fish

Tetrapodomorpha
Tiktaalik roseae

-Sauropterygia
Pliosaurus funkei
Pliosaurus kevani
Plesiosaurus dolichodeirus

-Mosasauroidea
Tylosaurus proriger

-Ichthyosauria
Ichthyosaurus communis
Stenopterygius sp.
Temnodontosaurus platyodon

-Crocodylomorphs
Metriorhynchus superciliosus

-Pterosauria
Quetzalcoatlus (in hiatus)
Rhamphorhynchus (in hiatus)

-Dinosauria
Citipati osmolskae
Velociraptor mongoliensis (in hiatus)
Dakotaraptor (Saurian backer exclusive)
Archaeopteryx (Kickstarter!)
Brachiosaurus (in hiatus)
Microraptor (in hiatus)

-Mammalia
Thylacinus cynocephalus (Coming soon)

There’s probably a bunch more I’ve forgotten but these are all the “official” Palaeoplushies I’ve made up to this point. I was going to stop when I reached Tiktaalik but I like Tetrapod fish too much.

SCIENTISTS CONFIRM THE PRESENCE OF LUNGS IN COELACANTHS

Coelacanths are lobe-finned fishes, that look somewhat like limbs. Known from the Devonian to Recent that were long considered extinct, until the discovery of two living species in deep marine waters of the Mozambique Channel and Sulawesi. Despite extensive studies, the pulmonary system of extant coelacanths has not been fully investigated.

Since its rediscovery in 1938, scientists doubted the existence of a lung in the living species West Indian Ocean coelacanth (Latimeria chalumnae) when compared with fossil species. 

Now, an international team of researchers confirm the presence of functional lungs at early embryonic stages; these lungs lose function and become vestigial lungs in adulthood. The finding sheds light on how ancient relatives may have lived about 410 million years ago.

Coelcanths is a heavily built fish living in rocky environments between 110 and 400 m deep in the coastal waters of the Mozambique Channel and of Sulawesi. This large animal (up to 2 m long) is ovoviviparous. The young develop in the oviduct of the female, which can give birth to 26 live pups of about 35 cm long. Juvenile coelacanths (below 80 cm long) are rarely observed or caught.  

The presence of a large calcified sheath in the abdominal cavity of fossil coelacanths has been known since the 19th century but was previously regarded as either an ‘internal osseous viscus’ (unknown internal organ), a bladder or swimbladder.  Only recently this organ has been formally described in fossils coelacanths as a pulmonary organ composed of large and rounded calcified plates, positioned ventrally relative to the gut, and with a single anterior opening under the opercle.  The parallel development of a fatty organ for buoyancy control suggests a unique adaptation to deep water. 


Three-dimensional reconstructions of the pulmonary complex of West Indian Ocean coelacanth (L. chalumnae) at different ontogenetic stages.

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Crypto-Biology and Unusual Creatures!

On December 22, 1938, Captain Hendrik Goosen caught an unusual fish of the coast of South Africa. He took it straight to port to local museum official and amateur scientist Marjorie Courtenay-Latimer, who recognized it as an extremely unusual creature and sought to identify it. 

Unable to locate anyone that day and facing the decomposition of the fish she had it stuffed and mounted. It wasn’t until the following February that a local university professor saw it and recognized its importance, naming the species after Latimer and the location it was found, the Chalumna River. The Coelacanth (Latimeria chalumnae) is a type of lobe finned fish that first evolved (and is present in the fossil record) over 400 million years ago. The name coelacanth was given by the great Swiss paleontologist Jean Louis Rodolphe Agassiz (1807-1873) and comes from the Ancient Greek word κοῖλ-ος (koilos) meaning hollow and ἄκανθ-α (akantha) meaning spine-the coelacanth has a very unusual central nervous system. The coelacanth was thought to have gone extinct at the end of the Cretaceous Period 65 million years ago. The coelacanth became the defining member (and still most famous member) of a class known as the Lazarus Taxon, species that disappear from the fossil record and are thought to be extinct only to be discovered after their period of supposed extinction. The coelacanth also enjoys minor celebrity status among Fundamentalist Christians, many of whom maintain that the coelacanth confirms that the fossil record is incomplete and not trustworthy, and many of whom use the coelacanth to assert that humans could also have lived alongside dinosaurs.

Video courtesy National Geographic.  Some users will see a brief ad, so sorry!  Note to parents:  extremely mild bleeped out cursing at first 15 seconds.

Happy Birthday, B! You are also a stunning wonder, and every day I am glad to be the one who pulled you out of the ocean, the rarest of treasures!

Lobe finned friends! Collect all 8?

Neoceratodus: Australian lungfish, living

Ichtyostega: early tetrapod, extinct

Protopterus: African lungfish, living

Periopththalmus: Mudskipper, one genus of many, living, convergently evolved bro.

Eusthenopteron: Large predatory lobe finned fish, extinct

Tiktaalik: Lobe finned fish/Tetrapod ancestor, exctinct

Latimeria: Coelacanth, living

Clarias: Walking catfish, living, convergently evolved bro

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Analogous anatomy between birds and humans

Both birds and humans are Tetrapods (four-footed/four-limbed), evolved from lobe-finned fishes in the Devonian era (approximately 400 million years ago).

Along with birds and humans, all other terrestrial vertebrates are also tetrapods, as are cetaceans (the whale family). In fact, cetaceans evolved long after tetrapods crawled out of the sea (a la Tiktaalik), from land-dwelling mammals that looked more like a cross between a crocodile and a small dog than any whale we know today.

Carl Zimmer has a fascinating book on the subject, called At The Water’s Edge: Fish with Fingers, Whales with Legs, and How Life Came Ashore but Then Went Back to Sea, which I recommend along with all of his other writing.

L'Histoire de la Nature des Oyseaux. Pierre Belon du Mans, 1555.

anonymous asked:

Could you maybe clarify all the terms on your cladogram? I mean I know that they're all defined by evolutionary relationship and stuff but maybe both define them AND provide an example animal? I'm just a little confused by some of the names...

Oh yeah, sure! 

Chordata (Brick Red): Tunicata + Craniata + Cephalochordata; their most recent common ancestor, and all its descendants. Typically characterized by having a notochord, a dorsal neural tube, pharyngeal slits, a post-anal tail, and an endostyle at some stage of their lives. Examples include hagfish, sea squirts, sharks, sea bass, lungfish, frogs, humans, birds, and lizards (all vertebrates are chordates). 

Vertebrata (Red): Myllokunmingia + Gnathostomata (+ MRCA and all descendants); typically all chordates that have a backbone. Includes: sharks, sea bass, lungfish, frogs, humans, birds, lizards, and lampreys. 

Gnathostomata (Brown): Chondrichthyes + Placodermi + Teleostomi (MRCA & des.; jawed vertebrates. Includes: Sharks, sea bass, lungfish, frogs, humans, birds, and lizards. 

Placodermi (Beige): All gnathostomes more closely related to Dunkleosteus than to any living “fish”; these are the “armoured fish” that had huge armor plating on their heads. All non-placoderm Gnathostomes are in Eugnathostomata. Includes Dunkleosteus; all are now extinct. 

Chondricthyes (Orange): All Eugnathostomatans more closely related to Carcharodon than to humans; is all cartilaginous fish. Originally it was thought that bony fish evolved from cartilaginous fish, however, it has since been found that both diverged from a common Placoderm ancestor. Includes sharks and rays. 

Teleostomi (Yellow): All Eugnathostomatans more closely related to humans than to Carcharodon; “bony fish”. Includes sea bass, lungfish, frogs, humans, birds, and lizards. It is subdivided into Acanthodii & Euteleostomi. 

Actinopterygii (Olive Green): All Euteleostomis more closely related to sea bass than to humans. “Ray-finned fish”. Includes sea bass, clownfish, tuna, and goldfish. 

Sarcopterygii (Lime Green): All Euteleostomis more closely related to humans than to sea bass. “Lobe-finned fish”. Includes lungfish, coelacanth, frogs, humans, birds, and lizards. 

Tetrapoda (Light Green): Frogs + Humans, MRCA & all its descendants. Essentially, all land vertebrates - there are many forms of lobe-finned fish that were able to crawl onto land that form Tetrapoda’s most recent ancestors, but tetropoda proper is just all the descendants of the MRCA for all modern land animals (amphibians, sauropsids, and mammals). Includes frogs, humans, birds, and lizards.

Lissamphibia (Green): Caecilians + Frogs, MRCA & all its descendants. Essentially amphibians, though it excludes many extinct amphibians (when you use the term amphibian to mean all non-amniote tetrapods). This might not actually be a proper cladistic group, but I included it as it definitely does not contain any amniotes. Includes caecilians, frogs, and salamanders. 

Amniota (Dark Green): Humans + Birds, MRCA & all its descendants. All hard-shelled-egg laying land animals (specifically, they produce an egg with an amnios, allowing the animal to lay the egg on land, rather than water). Even though many mammals (and some reptiles!) have secondarily lost this ability, their ancestors did have it, making them a part of this group. Includes humans, birds, and lizards. 

Synapsida (Seafoam): A group of amniotes that includes mammals and all amniotes more closely related to mammals than other living amniotes. Synapsids are not reptiles; though many non-mammalian synapsids resemble them heavily. They are easily characterized by their skulls: many amniotes have temporal fenestra (a hole behind their eye socket); synapsids only have one of these. Most reptiles have two. Includes Dimetrodon, humans, and whales. 

Mammalia (Teal): Platypus + Humans, MRCA & all its descendants. All mammals, essentially. Mammals are typically characterized by the ability to produce milk from mammary glands. Most don’t lay eggs, but either give birth to their young in a pouch (marsupials) or grow the young inside of a placenta (placentals, aka us). Includes echidnas, humans, whales, and kangaroos. 

Sauropsida (Aqua): All amniotes more closely related to birds than to mammals. Essentially reptiles. Since birds and dinosaurs are included in this group, there aren’t a whole heck of a lot of good unifying characteristics. Many sauropsids are endothermic (warm-blooded); many have feathers in addition to scales; and some even give birth to live young. Includes turtles, plesiosaurs, lizards, tuatara, snakes, mosasaurs, icthyosaurs, crocodiles, pterosaurs, dinosaurs, and because it includes dinosaurs, birds. 

Lepidosauria (Dark Purple): Lizards + Tuatara, MRCA & all its descendants. Characterized by having overlapping scales. A part of the larger group Lepidosauromorpha within Sauropsida. Includes lizards, tuatara, snakes, and mosasaurs. 

Squamata (Purple): Lizards + Snakes; MRCA & all its descendants. Characterized by skins with horny scales and shields, and can move the upper jaw as well as the lower jaw (not something most jawed vertebrates can do). Includes lizards, snakes, and mosasaurs. 

Mosasauridae (Lavender): Mosasaurus + Plioplatecarpus, MRCA & all its descendants. The mosasaurs - large marine reptiles, similar to monitor lizards, but elongated and streamlined for swimming. Extinct now. Includes - you guessed it - Mosasaurus, as well as Tylosaurus and many others. 

Serpentes (Fuchsia): Blind snakes + Vipers, MRCA & all its descendants. Essentially all snakes. They’re distinct from lizards due to lack of eyelids and external ears - there are many legless lizards, but snakes are a specific group of “lizards” (given that squamates on the whole can be called lizards). Includes the garter snake, blind snakes, and cobras.  

Ichthyosauria (Hot Pink): All animals more closely related to Icthyosaurus than to Grippia; essentially, a group of sauropsids not a part of Lepidosauromorpha or Archosauromorpha. They were adapted for completely aquatic life and are now completely extinct; they sort of looked like dolphins. Includes Icthyosaurus, Opthalmasaurus, and Mixosaurus. 

Archosauromorpha (Azure): Birds + Crocodiles + Turtles, MRCA & all its descendants. Essentially all modern sauroposids more closely related to birds than to lizards, though of course it includes many extinct groups as well that are descended from their most recent common ancestor. This is a very diverse group with a wide variety of characteristics. Includes turtles, plesiosaurs, crocodiles, pterosaurs, dinosaurs and therefore birds. 

Pantestudines (Dark Violet): All sauropsids more closely related to turtles than any other animal. A group of archosaurimorphs. Genetic analyses have shown strong evidence that they are more closely related to archosaurs than to lepidosaurs; these genetic analyses that include fossils also reveal that animals such as plesiosaurs and placodonts are in this group. Includes turtles, plesiosaurs, Liopleurodon, and Placodus.   

Plesiosauria (Plum): Plesiosaurus + Peloneustes, MRCA & all its descendants. The plesiosaurs - the long-necked (though many lost this) marine reptiles from the Mesozoic. This group also includes the pliosaurs, which on the whole lost the long necks characterizing the group. Includes Plesiosaurus, Elasmosaurus, Kronosaurus, and Liopleurodon. 

Testudines (Violet): Xinjianchelys + Trionyx, MRCA & all its descendants. Essentially, all modern turtles - characterized by having a shell developed from the ribs that acts as a shield. The classification of turtles has been a struggle, given that they are anapsids - meaning, they have no temporal fenestra. The earliest amniotes were anapsids and it was assumed from fossil evidence that turtles, therefore, were descended directly from them, and were not part of any more derived amniote groups (such as synapsids or archosaurs). Most sauropsids are diapsids - meaning, they have two temporal fenestrae. It has since been theorized, however, that turtle ancestors were diapsids; turtles actually lost their temporal fenestrae during their evolution. This is not a completely ridiculous idea, of course; many traits are secondarily lost in groups, making classification by traits a nightmare and unfeasible. Genetic analyses have revealed that the closest living relatives for turtles are crocodiles and birds, making them a part of Archosauromorpha. Includes Green sea turtles, the African spurred tortoise, and terrapins such as the Red-eared turtle. 

Archosauria (Cerulean): Crocodiles + Birds, MRCA & all its descendants. Characterized by having teeth in sockets, though some archosaurs (such as birds) lost their teeth secondarily. Many members of the group have erect or partially erect gaits, unlike other sauropsids, which have sprawling gaits (such as lizards). Archosaurs were the dominant land vertebrates for the entirety of the Mesozoic Era (though dinosaurs were only really during the Jurassic and Cretaceous; a wide variety of archosaurs were common throughout the Triassic). Given that birds are far more diverse than mammals; it can still be argued that archosaurs continue to be the dominant land vertebrates today. Includes crocodiles, pterosaurs, dinosaurs and therefore birds. 

Pseudosuchia (Aqua): Living crocodilians and all archosaurs more closely related to crocodilians than birds. They have massively built skulls, and many still have the typical reptilian sprawl, though some have an erect gait. They typically also had armored plates. Includes crocodiles, alligators, Deinosuchus, phytosaurs, and aetosaurs. 

Ornithodira (Indigo): A subgroup of Avemetatarsalians, which is all archosaurs more closely related to birds than to crocodiles. Ornithodira is, specifically, Dinosaurs + Pterosaurs, MRCA, and all descendants (Ornithodira was easier to fit into the diagram). This group potentially has protofeathers as a characteristic of the entire clade, though many lost them secondarily (such as hadrosaurs). Includes almost all flying vertebrates. Members include Scleromochlus, all pterosaurs, all dinosaurs and therefore all birds.  

Pterosauria (Blue-Violet): Anurognathus + Preondactylus + Quetzalcoatlus, MRCA & Descendants. The pterosaurs. These are all of the “flying reptiles” that one typically knows about from the Mesozoic Era. They had pycnofibres - small filaments similar to hair, potentially the same as protofeathers; and flew using membraneous wings that stretched across an extended finger. Includes Dimorphodon, Pteranodon, Pterodactylus (”pterodactyl”), and Ornithocheirus. 

Dinosauria (Blue): Megalosaurus + Iguanodon, MRCA & descendants. All dinosaurs. Note that this does not include many of the animals listed above! Dinosaurs are a very specific group of animals that all, typically, were able to walk with the limbs directly beneath the body. Protofeathers were also an ancestral trait for this group, though many dinosaurs secondarily lost them - the same proteins that make protofeathers were turned into scales. Includes Brontosaurus (yes, it’s a thing again, there was a study this year), Stegosaurus, Triceratops, Tyrannosaurus, Allosaurus, Velociraptor, Brachiosaurus, Troodon, Parasaurolophus, Ankylosaurus, Pachycephalosaurus, Archaeopteryx, the Dodo, Bald Eagles, Emus, Cassowaries, Chickens, Ducks, Finches, Parrots, Robins, Crows, Geese, Blue Jays, Penguins, Auks, Seagulls… 

Avialae (Light Blue): All dinosaurs more closely related to modern birds than to Troodon. This is typically the group I mean when I say “birds,” though the clade that includes only modern birds is called Neornithes - all non-Neornithes Avialaens are extinct. Many basal Avialae, furthermore, are almost indistinguishable from their closest dinosaurian relatives, the troodontids. It is uncertain whether the earliest Avialaens (such as Archaeopteryx) could properly fly. Includes Archaeopteryx, Confuciusornis, Hesperornis, the Dodo, Bald eagles Emus, Cassowaries, Chickens, Ducks, Finches, Parrots, Robins, Crows, Geese, Blue Jays, Penguins, Auks, Seagulls… essentially, all birds. 

I hope that was helpful!

twerkyvulture  asked:

Some cryptozoologists like to claim that certain creatures thought to be extinct could still be lurking in far-flung corners of the world, or even right under our noses... but are there really any extinct species for which this could be possible?

The rediscovery of a species once thought extinct has happened many times before.  Such species - ones that reappear after supposedly going extinct - are called “Lazarus taxa”.

Most Lazarus taxa are rediscovered after relatively short periods of time, and their supposed extinctions are usually thought to have been caused by human activity.  Exceptions to this rule exist - most famously, the coelacanth.  

(Photo by Mark V. Erdmann)

Coelacanths are lobe-finned fish that originated in the Devonian period, around 400 million years ago.  They were thought to have gone extinct after the Cretaceous period, along with all non-avian dinosaurs.  That all changed in 1938, when a living coelacanth was caught off the coast of South Africa, essentially unchanged from the Devonian.

Coelacanths live at an extreme depth, where conditions stay relatively stable.  It’s believed that this is what allowed them to survive numerous mass extinctions - even those which devastated most marine ecosystems.

Coelacanths aren’t the only marine animals to survive in such a manner.  The cephalopod order Vampyromorphida was widespread throughout the world’s oceans during the Mesozoic period, but went almost entirely extinct after the Cretaceous.  The only survivor - Vampyroteuthis infernalis, or the “vampire squid” - lives in the deep-sea abyss, where conditions stay relatively unchanged.

While the possible answers to your question are so numerous that I can’t even begin to pick from them, I will say this: If you’re looking for living fossils, I’d start by taking a dive.

Originally posted by oceansprincess

Happy Darwin Day!!!
Here’s a fact to get you thinking about evolution on the master’s birthday:
Some fish are more closely related to us than they are to other species of fish!
Lobe-finned fishes, like lungfish, share a more recent common ancestor with tetrapods (that includes us!) than they do with ray-finned and cartilaginous fishes, like tuna and sharks.

We were curious, what books does a Ph.D. student in comparative biology recommend? So we asked them! Below are picks of favorite science books from three of the Museum’s Richard Gilder Graduate School students:

  • Bully for Brontosaurus by Stephen Jay Gould, recommended by Zac Calamari 
    • “A book of short essays on natural history and evolution that showcases Gould’s talent for popular science writing. Great for when you need a short, entertaining read.

“
  • The Most Human Human: What Artificial Intelligence Teaches Us about Being Alive by Brian Christian, recommended by Aki Watanabe
    • “Brian Christian writes about his unique experience being a judge in the annual Turing test, where programmers compete by building artificial intelligence that can have “normal” conversations with humans. Not only does the book explore the historical development of AIs, but Christian completely alters the the readers’ perspective by describing how advancements in making human-like AIs informs us about what makes us humans “human.” Are we becoming less “human” as we depend more on computers?”
  • Your Inner Fish by Neil Shubin, recommended by Allison Bronson 
    • “An approachable primer on evolutionary developmental biology, but also on paleontology. As the title implies, it’s a look into human evolutionary history, with a focus on the many features we share with lobe-finned fishes.”

Get more science-reading recommendations.

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Finding the Rarest Fish in the Ocean

On December 22, 1938, Captain Hendrik Goosen caught an unusual fish of the coast of South Africa. He took it straight to port to local museum official and amateur scientist Marjorie Courtenay-Latimer, who recognized it as an extremely unusual creature and sought to identify it. Unable to locate anyone that day and facing the decomposition of the fish she had it stuffed and mounted. It wasn’t until the following February that a local university professor saw it and recognized its importance, naming the species after Latimer and the location it was found, the Chalumna River. The Coelacanth (Latimeria chalumnae) is a type of lobe finned fish that first evolved (and is present in the fossil record) over 400 million years ago. The name coelacanth was given by the great Swiss paleontologist Jean Louis Rodolphe Agassiz (1807-1873) and comes from the Ancient Greek word κοῖλ-ος (koilos) meaning hollow and ἄκανθ-α (akantha) meaning spine-the coelacanth has a very unusual central nervous system. The coelacanth was thought to have gone extinct at the end of the Cretaceous Period 65 million years ago. The coelacanth became the defining member (and still most famous member) of a class known as the Lazarus Taxon, species that disappear from the fossil record and are thought to be extinct only to be discovered after their period of supposed extinction. The coelacanth also enjoys minor celebrity status among Fundamentalist Christians, many of whom maintain that the coelacanth confirms that the fossil record is incomplete and not trustworthy, and many of whom use the coelacanth to assert that humans could also have lived alongside dinosaurs.

Video courtesy National Geographic.  Some users will see a brief ad, so sorry!  Note to parents:  extremely mild bleeped out cursing at first 15 seconds.

Happy Birthday, B! You are also a stunning wonder, and every day I am glad to be the one who pulled you out of the ocean, the rarest of treasures!

mmmsammishes  asked:

I just saw your Gar photoset and I was like, are Gars and Coelacanths related? (Literally the extent of my knowledge on fish is strictly from playing Animal Crossing)

It’s ok, I learned to ID a lot of fish through playing Okami. Thank god for the No Cartoon Fish trope.

Now, on to your question. Gars and coelacanths are not actually closely related, even though both are actually known as “living fossil” species due to the characteristics they share with primitive/extinct species of fish.

Coelacanths actually belong to a class called Sarcopterygii, the lobe-finned fishes, while gars belong to the class called Actinopterygii, the ray-finned fishes. Here is a diagram of the difference between lobe and ray fins:

The most important thing to notice is that the lobe fin (on the left) has dense bony projections within its fin, while the ray fin (on the right) merely has the slender fin ray bones. This is REALLY important, because lobe-finned fishes would later use those bony projections to make an entirely new type of limb… a foot!

Hell yeah, feet!!!

In fact, if you look at a fish phylogeny, you will come to realize that not only are we more closely related to lobe-finned fishes like the coelacanth than ray-fins like the gar, our clade- the tetrapods- is actually still nested within Sarcopterygii. In other words, you are still technically a fish.

That’s right- we are hot, sexy, teleostomic fish. And we are more closely related to coelacanths than they are to gars.

Permian scene

During the Permian, the Earth bakes and desiccates. Seas dry into deserts that drift across Pangea, leaving just pockets of green where lakes pool and streams list beneath Dawn World forests. Here amphibians float and meander, scuttle in the mud, and feed on fish and worms, or skulk in the underbrush to munch on vegetables and bugs. Diplocaulus, Diadectes, Eryops—their names sound like how they move, waddling, undulating, bobbing. There’s still some tadpole in them. 

Eryops is like a mammoth frog, though the fat tail, squat legs, and scalpel teeth suggest crocodile. It’s too big to breathe through its skin, so throat pouches balloon and deflate under its chin. It likes to pull millipedes from the leaf litter or corner fat fish in the shallows. Eryops is a bully. 

But bullies are not immune to the food chain. Orthacanthus swims here too. It’s eel-like, with twin-forked teeth—not an amphibian, but a freshwater shark whose reign as apex predator lasts 175 million years, from the Devonian to the Carboniferous to the Permian, where it slithers after Eryops who have grown too relaxed, too careless, then snags them with its mouthful of fishhooks. The prongs tear flesh messily, turn meat into uneven ribbons. The shark’s prey chokes, writhes, tries to swim away, but fails, bleeds out, dies. Orthacanthus feeds until it cannot. Then the others come—other amphibians, once-bullied lobe-finned fish, swimming insects, even late summer pollywogs—and dine until the Eryops is just a clatter of bones tangled among the weeds and fallen trees of the desert-fenced bayou.