The most plausible hypothesis is: Tropical regions generally have more available water and higher levels of solar radiation. They also have very high rates of immigration and very low rates of extinction.
explanation:
Water is essential for an abundance of life, and sunlight is the means by which the whole food chain receives energy. Plants convert the sunlight into food, herbivores eat them, and other animals eat herbivores.
Hope this helps, and muchas luck on your biology.
The fossil record shows a sequence from simple bacteria to more complicated organisms through time, it is very reliable because it is physical evidence and by studying fossils, scientists can learn how much (or how little) organisms have changed as life developed on Earth.
True, your legs are examples of levers.
<span>I am pretty sure its the diaphragm, but its not located behind the lungs its below the lungs. </span>