And since then, have remained largely unchanged as they managed to survive by adapting a very key skill: they eat everything! Life restoration of Mimoperadectes.
Possums are dietary generalists. They will eat anything, and I mean anything : trash, bugs, even broccoli! This is an adaptability that lets possums live just about anywhere they want in the world. They love all types of cuisine. Even rotten food! Brachiopods have hung on in whatever crevices they could attach to but never managed to regain their dominance. Today these trees are represented only by one species, Ginkgo biloba , but this tree with fan-shaped leaves had its heyday when ferns, cycads and Jurassic dinosaurs dominated the landscape.
Modern Ginkgo trees are not very different from those that herbivorous dinosaurs may have fed on. A recent Paleobiology study by Wesleyan University paleobotanist Dana Royer and colleagues found that Ginkgo trees seem to do best in disturbed habitats alongside streams and levees, a habitat preference that may have been their downfall.
Scientists know from living Ginkgo trees that they grow slowly, start reproducing late and are generally reproductive slowpokes when compared to more recently evolved lineages of plants that live in the same places. Ginkgo trees may have simply been out-bred by other plants when suitable habitats opened up, but this makes it all the more remarkable that one species managed to survive to the present day. The duck-billed platypus truly looks as if it belongs to another era, if not another planet.
In fact, when 19th-century European naturalists first saw stuffed specimens sent from Australia, some scholars thought the animals must be a joke.
Monotremes, like the platypus, are strange mammals. These archaic, egg-laying forms last shared a common ancestor with marsupial and placental mammals over million years ago, and rare fossils from Australia indicate that there have been platypus-like forms since million years ago.
Though often reconstructed with a narrower-snout, the Late Cretaceous Steropodon was a close cousin of early platypuses.
A much closer relative to the modern platypus, known as Obdurodon , has been found in more recent rocks spanning about 25 to 5 million years ago.
This animal is different from its living relative in retaining adult teeth and some particular skull characteristics, but the skull shape is strikingly similar. Rather than being a new kind of creature that evolved after the dinosaurs, the duck-billed platypus is truly a more archaic kind of mammal with roots that go far deeper than most other mammals on the planet.
Coelacanths were supposed to be dead. As it would turn out, the fish was a living coelacanth—she might as well have found a living Tyrannosaurus. Paleontologists have discovered fossil coelacanths younger than 65 million years old since , but, since these were unknown when the fish was re-discovered off South Africa, the discovery of a living member of the group immediately catapulted the fish to fame.
Two species have since been recognized, and they are different than their prehistoric relatives—enough to belong to a different genus, Latimeria —but they are still quite similar to their prehistoric cousins. Creatures recognizable as coelacanths go back to about million years ago, and these fleshy-finned fish were the evolutionary cousins of lungfish and our own archaic forerunners—the very first vertebrates to walk on land were specialized lobe-finned fish related to the recently discovered Tiktaalik.
Like many other organisms on this list, though, living coelacanths are the last of a once more widespread and varied lineage. The earliest fossil records of sponges date back to about million years ago. These well-preserved fossil sponges were thought to be the oldest until a million year old fossil was found in The new find challenges what scientists currently know about the timing of animal evolution.
Until a few years ago, sponges were thought to be the first animals on the evolutionary tree. However, newer research suggests that ctenophores comb jellies are the first true animals , not sponges. The National Institute of Health NIH spearheaded this research into comb jellies to aid in research on animals as models for human diseases.
Over half of the known disease genes in humans are present in comb jellies. Age: disputed — possibly 3. Cyanobacteria are the oldest existing species in the world. Fossilized stromatolites — a type of layered rock made up of microbial mats of microorganisms — dating back to over 3. However, this evidence is disputed and as of , the oldest undisputed evidence of cyanobacteria is 2. Cyanobacteria live in almost every terrestrial and aquatic habitat in the world, including, oceans, damp soil, desert rocks that were temporarily wet, and even Antarctic rocks.
They are known for their blue-green color, especially aquatic cyanobacteria, which can form highly visible and colorful blooms. Your email address will not be published. Save my name, email, and website in this browser for the next time I comment. Home Animals 10 Oldest Species in the World. Spread the love. This allowed sharks to dominate, giving rise to a whole variety of shapes and forms. Some of the most bizarre prehistoric 'sharks' to appear during this time actually evolved out of the chimaera lineage.
These include Stethacanthus , which had a truly peculiar anvil-shaped fin on its back, Helicoprion with a spiral buzz saw-like bottom jaw, and Falcatus , in which the males had a long spine jutting out of the back and over the top of the head.
Modern-day chimaeras are much less diverse and typically live in the deep ocean. Growing up to 1. Their upper jaw is fused with the skull, and most chimaera also have venomous spines.
But a handful of shark lineages persisted. By the Early Jurassic Period million years ago the oldest-known group of modern sharks, the Hexanchiformes or sixgill sharks, had evolved.
They were followed during the rest of the Jurassic by most modern shark groups. It was at this point that they evolved flexible, protruding jaws, allowing the animals to eat prey bigger than themselves, while also evolving the ability to swim faster.
At the beginning Cretaceous of Period million to 66 million years ago sharks were once again widely common and varied in the ancient seas, before experiencing their fifth mass extinction event. While much of life became extinct during the End-Cretaceous extinction event, including all non-avian dinosaurs, sharks once again persisted. But they were still affected. Fossil teeth show that the asteroid strike at the end of the Cretaceous killed off many of the largest species of shark.
Only the smallest and deep-water species that fed primarily on fish survived. Sharks soon began to increase in size once again, and continued to evolve larger forms throughout the Palaeogene 66 to 23 million years ago. It was during this time that Otodus obliquus , the ancestor to megalodon Otodus megalodon , appeared.
Despite what many might think, megalodon is not related to great white sharks. In fact it may have been in competition with the great white shark's ancestors, which evolved during the Middle Eocene 45 million years ago from broad-toothed mako sharks. There are at least eight different species of hammerhead shark, and while fossil teeth evidence suggests that their ancestors may have existed 45 million years ago, molecular data points to a much more recent appearance during the Neogene which began 23 million years ago.
The strange shape of their head is thought to mainly help in electroreception the detection of naturally occurring electric fields or currents as they hunt for prey.
It may also improve their vision, enhance their swimming and refine their ability to smell. Since the End-Cretaceous mass extinction, sharks have come to dominate the oceans once again, returning to the role of apex predator along with large marine mammals.
Because most of the skeleton of sharks is made from soft cartilage, it takes special conditions for this to preserve. The teeth, however, are made from a much tougher material known as dentin, which is harder and denser even than bone.
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