Can you please answer some questions on biology please? Thank you!
1. What allowed birds and mammals to become dominate vertebrates?
2. How did extinction and continental drift shape evolution?
3. What was the most successful vertebrate on the early earth?
1. Evolution allowed the birds and mammals to become the dominant vertebrates on this planet. Jawless fish gave rise to early amphibians who evolved into reptiles and further into mammals and dinosaurs (who later evolved into birds). Evolution was aided by extinction events and continental drift. Land provided many more food options compared to the ocean (although life evolved in oceans) and hence mammals and birds came to dominate the vertebrate class. Another advantage that mammals have over other species is the larger brain size, allowing them better evolution possibilities.
2. Continental drift refers to the constant movement of tectonic plates. The Earth's crust is divided into a number of tectonic plates, all of which were originally connected together to form Pangea, but started moving apart, giving the current shape to the land masses. This drift causes the formation of mountains or subduction zones.
Extinction often involves mass destruction events that cause the extinction of species. There have been five major extinction events in history: the extinction of jawless fish and marine invertebrates due to possible habitat change (430 million years ago), global cooling (~360 million years ago), volcanic eruption leading to the destruction of mammals and amphibians (~248 million years ago), the extinction of early dinosaurs, marine vertebrates and mammals (213 million years ago) and the extinction of dinosaurs due to a meteor strike and volcanic activity (65 million years ago).
Extinction removed the older species and provided chances to new species. The continental drift caused new ecosystems to form and thus new species came into being. The surviving species evolved and learned to survive in new ecosystems. An example is how after the extinction of dinosaurs, species similar to modern day crocodiles and birds evolved. An example of new ecosystems is the grasslands available on all the continents, where evolution (such as distance-vision and speed) was required for successful survival.
3. Ray-finned fish are the most successful vertebrates. There are almost 20,000 living species of ray-finned fish. Bony fish were the most successful of vertebrates on the early earth. Bony fish gave rise to (or evolved into) reptiles who dominated the surface for millions of years.