Which of Today's Animals Lived Alongside Dinosaurs?

to fill the atmosphere. This in turn created what's called an impact winter, in which life giving light from the sun was blocked. A plant life couldn't photosynthesize and thus died off. The oceans acidified, the food chain was disrupted, and some seventy to eighty percent of all life on the planet was wiped out. It was the literal end of an era, the Mesozoic to be specific. The mighty non avian dinosaurs were perhaps the most famous of the life forms that died out post asteroid, but many others

became extinct as well. These included aquatic reptiles like plesiosaurs, the first vertebrate animals to fly by flapping their wings. The pterosaurs, the vast numbers of oceanic invertebrates, and some ninety percent of algae species. Life was never the same, but some types of animals weren't hit nearly as hard. At least a few members of about eighty four percent of marine families and eighty two percent of land vertebrate

families made it through. So many life forms survived the event that it would take way more than a podcast episode to describe them all, and many of the animals have descendants that still live today. Some of these species look a lot like their Mesozoic counterparts. Others have changed quite a bit, including birds, which are the descendants of avian dinosaurs that managed to survive the extinction event. So aside from birds, which of today's animals walked, crawled, slithered,

or swam alongside dinosaurs. Dinos lived on Earth during the Mesozoic Era, which lasted from two hundred and forty eight to sixty six million years ago. Geologists divide the Mesozoic Era into three periods, from longest ago to most recent the Triassic, Jurassic, and Cretaceous. Dinosaurs became more diverse as time went by, and at the same time, other life forms developed and became extinct. If the Mesozoic era was the age of the dinosaurs, the next era, the Cenozoic era,

was the age of mammals. The first mammals were monotremes, or mammals that reproduce by laying eggs. Mammals in general are common today, but only three monotrem species still exist. These are the duckbilled platypus and a couple of echidnas, and you can see our past episodes on both of those. Many types of reptiles species die during the extinction event, but some snakes, lizards, and crocodilians persevered. Crocodilians have been on the planet for about two hundred and forty million years.

There are twenty three crocodilian species today, including alligators, crocodiles, and caymans. Mesozoic crocodilians were generally larger. Another prehistoric order of reptiles is the Saphenodontians. Today there is one living sphenodon, the Tuitara, a small, spiky, gray green reptile that lives in New Zealand. The most likely evolutionary origin for these reptiles is that in the distant past they arose from amphibians. Very large amphibian species lived before and during the Mesozoic.

These are gone today, but in their place three primary types of amphibians survived, frogs and toads, nuts and salamanders, and celions, which are animals that mostly look like worms but have skeletons. But not. Every family that lived during the Mesozoic has only a few descendants left today. All modern insect groups existed before or arose during the Mesozoic era, and perhaps most notable of these is the usocial bee

of bees that live in colonies. Most likely these evolved along with flowering plants, which started to develop in the Cretaceous period. Without this code development, we humans wouldn't have honey or a whole host of bee pollinated fruits, vegetables, nuts, and grains today. Ferns and conifers were also widespread during the Mesozoic era, and ferns actually experienced a huge population

spike after the extinction event. Then there's Gingo biloba. If you see one of these trees but which has fan shaped green leaves that turn golden yellow in the fall, you're looking at a plant that's almost identical in appearance to its Mesozoic ancestors, but the oceans were particularly devastated by the event. Dinosaurs were not particularly aquatic, but there were lots of sea dwelling animals during the Mesozoic. The

aforementioned pleasyosaurs were long necked, finned reptiles. Think of the Lochness monster and you've got a pretty good idea of what one looked like, though as far as science knows, they did not survive. Other marine life forms experienced heavy losses but eventually recovered and went on to thrive and diversify. Those include the echinoderms like sea stars, sea urchins, and sea cucumbers, plus mollusks with their soft bodies and hard shells.

The clams, snails, lobsters, crabs, and shrimp that make their way to the mouths of oceanic carnivores, and the plates of hungry humans come from predecessors that, one way or another, lived through the extinction event. Sharks also inhabited the world's oceans long before the first dino made its way across land, and they're among the most well known oceanic predators today, but a few of today's species are the only remaining

examples of long extinct marine families. The most famous may be the Sila camp, the last known marines sarcopterrigian, which were lobe finned bony fish. There are plenty of other Sarcopterygians in the world, though. All of the four limbed vertebrates on the planet, from turtles to tucans to humans, arose from common ancestors that diverged from the sarcoptigians long

before the Mesozoic era. Scientists thought selacanths were extinct until the nineteen thirties, so hey, it's possible that researchers may one day find other remnants of Mesoic life out there. Today's episode is based on the article which of today's animals lived alongside dinosaurs on how stuffworks dot Com, written by Tracy V. Wilson. Brain Stuff is production of by Heart Radio in partnership with how Stuffworks dot Com, produced

by Tyler Klang. For more podcasts from my Heart Radio, visit the iHeartRadio app, Apple Podcasts, or wherever you listen to your favorite shows.