Modern birds, or neornithine birds, exhibit features such as a lightweight skeleton, advanced respiratory systems, and a high metabolic rate, allowing for efficient flight and diverse ecological adaptations. In contrast, ancient birds, like Archaeopteryx, possessed characteristics of both dinosaurs and modern birds, including teeth, long bony tails, and feathers that were not exclusively for flight. Additionally, many ancient birds had a different ecological role and morphology, reflecting their evolution during the Mesozoic era. Overall, modern birds show greater specialization and diversity compared to their ancient counterparts.
This I a very silly question.
well, a bird that cant fly has a larger body mass than one that can
Ancient birds
Seals are marine mammals; penguins are sea birds.
A bird lays eggs and a mammal doesn't
There are many differances between the two. Dinosaurs were warmblooded, whereas reptiles are coldblooded. Reptiles also have legs that come out at right angles to their body, and a unusual knee structure. Dinosaurs had leg and hip structures close to that of modern mamals in the case of the herbavores and birds in the case of carnivores.
Native birds have always been in their current location. Introduced birds have been brought in from elsewhere - either deliberately or accidentally.
1. Mammals have fur; birds have feathers. 2. Mammals produce milk; birds do not. 3. Mammals are synapsids by descent; birds are diapsids by descent.
Stocism is the art of hunting little birds, Epicureanism is the art of touching dogs.
Some can fly some can not Some can swim some can not Birds beaks are of different shapes Birds Wings are of different shapes Birds legs and feet are of different shapes Birds come in different sizes Some birds hunt prey on the wing
Bats are mammals, birds are not. Birds lay eggs, bats do not.
Birds and reptiles.