For example, pterosaurs started out with mouths full of teeth, but over time evolved a
lighter, toothless, beak-like mouth
. They also evolved a lung-airsac system similar to but predating that of birds by some 70 million years, that allowed efficient oxygen exchange for powered flight.
Neither birds nor bats, pterosaurs were reptiles,
close cousins of dinosaurs
who evolved on a separate branch of the reptile family tree. They were also the first animals after insects to evolve powered flight—not just leaping or gliding, but flapping their wings to generate lift and travel through the air.
Today’s scientific consensus is that pterosaurs are
nonetheless more closely related to dinosaurs
, whose living descendants are birds, than to any other group, including the next-closest, crocodiles.
Although the living reptiles birds are most closely related to are crocodilians (archosaurs), when it comes to their relation to dinosaurs, birds evolved from theropod dinosaurs. These theropods share over 100 traits with modern birds.
What is the relationship between birds and dinosaurs?
Birds evolved
What two periods did dinosaurs rule the earth?
The ‘Age of Dinosaurs’ (the Mesozoic Era) included three consecutive geologic time periods (
the Triassic, Jurassic, and Cretaceous Periods
).
Are ichthyosaurs Diapsids?
Ichthyosaurs are superficially dolphin-like reptiles that were important marine predators from the Triassic Period through the middle of the Cretaceous Period. … For now, paleontologists think that ichthyosaurs are diapsids, but exactly where they fit in the diapsid tree
is not yet known
.
Are sharks dinosaurs?
Today’s sharks are
descended from relatives that swam alongside dinosaurs in prehistoric times
. … It lived just after the dinosaurs, 23 million years ago, and only went extinct 2.6 million years ago.
What was the first bird on earth?
Archaeopteryx
is the earliest undisputed bird. A weak flyer, it shared characteristics with its dinosaur ancestors. Fossils show that Archaeopteryx , like dinosaurs, had teeth, a long bony tail, and grasping claws on its wings, but also had a bird-style hip and feathers.
Are there any dinosaurs alive today?
Other than birds, however,
there is no scientific evidence that any dinosaurs
, such as Tyrannosaurus, Velociraptor, Apatosaurus, Stegosaurus, or Triceratops, are still alive. These, and all other non-avian dinosaurs became extinct at least 65 million years ago at the end of the Cretaceous Period.
What is the most prehistoric bird alive today?
The Shoebill, Balaeniceps rex, also known as Whalehead, is a very large bird related to the storks. It derives its name from its massive shoe-shaped bill. The Shoebill is a very large bird, averaging 1.2 metres (4 ft) tall, 5.6 kilograms (12.3 lbs) and a 2.33 metres (7.7 ft) wingspan.
Are birds modern day dinosaurs?
Today,
all non-avian dinosaurs are long extinct
. … “All of the species of birds we have today are descendants of one lineage of dinosaur: the theropod dinosaurs.”
Did dinosaurs live on Pangea?
Dinosaurs lived on all of the continents
. At the beginning of the age of dinosaurs (during the Triassic Period, about 230 million years ago), the continents were arranged together as a single supercontinent
What was before dinosaurs?
The age immediately prior to the dinosaurs was called
the Permian
. Although there were amphibious reptiles, early versions of the dinosaurs, the dominant life form was the trilobite, visually somewhere between a wood louse and an armadillo. In their heyday there were 15,000 kinds of trilobite.
Which era do we live in?
Officially, we live in the Meghalayan age (which began 4,200 years ago) of
the Holocene epoch
. The Holocene falls in the Quaternary period (2.6m years ago) of the Cenozoic era (66m) in the Phanerozoic eon (541m).
