So can we say that birds are dinosaurs? If we say that, won't we confuse laymen? Even with the discovery of Archaeopteryx inthe dinosaur origin of birds was far from being accepted as fact. It's only really since Ostrom demonstrated the similarities between Archaeopteryx and Deinonychus in the late 60s that the theory has gained any respectability - and so, the idea that the dinosaurs even might include birds dates back only a few decades.
Are you sure you want to delete this answer? Yes Sorry, something has gone wrong. We simply do not know. All amniotes have internal fertilization, but not all of them have copulatory organs.
Those that have copulatory organs show differences in those organs that would suggest that they evolved independently of each other.
Crocodilians are more closely related to birds and to the tuatara than they are to the turtles, but turtles and crocodilians have single, centrally located penises, but most birds and the tuatara do not even have a penis The lizards and snakes are closely related to the tuatara, but lizards and snakes have paired hemipenes, one on each side.
It is obvious from the distribution and anatomy of this organ that the last common ancestor of tuataras, lizards, crocodilians and turtles probably lacked this organ.
Since no dinosaur has been found with a penile bone, and since soft body parts are rarely preserved as fossils, we simply do not know whether they have copulatory organs like crocs, turtles, lizards and snakes, or whether they are like the tuatara and most birds in having no penis at all.
Some people claim that dinosaurs are the closest relatives of birds a claim that is hotly debated and they also claim that the last common ancestor of all birds had a penis but that it has been lost independently in most birds that don't have them.
Then they take these two "facts" which are merely unsupported speculation and suggest that dinosaurs probably had copulatory organs. Such an argument is flawed because it relies on dogma, i.
Besides, since copulatory organs are beneficial, it is difficult to understand how they could have been lost through evolution so many different times among living birds, especially since reproduction would probably suffer in the transitional stage from penis to no penis.
What used to be a surefire procedure now becomes a lot less certain if two birds have to line up their cloacal openings and sperm is then squirted inside the female's body, when they used to use a copulatory organ and simply cannot miss.
Why would so many birds risk reproductive failure just to save a small, insignificant amount of body mass? Whether the last common ancestor of birds had a penis or not, and whether birds are descendants of dinosaurs or not, it really has no bearing on how dinosaurs mated.
It is possible that all of the dinosaurs evolved copulatory organs and it is also possible that none had them. It is also possible that some did and some did not.
We may never know.Another question surrounding dinosaurs is whether or not they were warm-blooded, like birds, or cold-blooded, like reptiles. The discovery of some new fossils and more research could help shed light on . Truly modern birds appeared emerged million years ago, way before the massive extinction which wiped out the dinosaurs.
While they were never really on top of the food chain, they are the only branch of dinosaurs to survive past the Cretaceous (if you haven’t already, get used to the idea: birds are dinosaurs). The popular belief in dino-to-bird evolution is based on a flawed cladistics analysis.
Some 'feathered dinosaurs' are likely true birds like Archaeopteryx, while others do not have real feathers. May 11, · Whether the last common ancestor of birds had a penis or not, and whether birds are descendants of dinosaurs or not, it really has no bearing on how dinosaurs mated.
It is possible that all of the dinosaurs evolved copulatory organs and it is also possible that none had kaja-net.com: Resolved. Apr 06, · Because of the current framework of classification, birds can be called "avian theropod dinosaurs".
I believe that birds and certain lines within the order Sarrischia evolved from a common ancestor, but not one from the other. Dinosaurs and Birds Are birds really dinosaurs or are they simply related?
That is a question that has gained new life in recent years due to the overwhelming facts the are pouring in from newly found fossils and studies from .