They might not have been able to adapt.
if we dont fell any thing it will ALWAYS BE NATURAL
Not necessarily. While adaptations can help an organism survive and reproduce in its environment, they may not always be beneficial in all situations or environments. Changes in the environment or interactions with other species can render an adaptation less useful or even harmful over time.
Every animal is always evolving, but we can not see it because it take many years. Only in a state of Hardy-Weinberg equilibrium, is when evolution does not occur. Animals are always are trying to be the most fit for their environment. Also the animal has no say in Natural Selection, the environment will chose the best animal for it's environment. Animals that are maladapted, or not suited for their immediate environment will die. Also an animal can be the best suited for it's environment, but if it can not reproduce there is no way those genes can be passed on to the next generation.
Many different species have evolved through natural selection, including finches, peppered moths, giraffes, and bacteria. Natural selection is a key mechanism in evolution that favors traits that improve an organism's chances of survival and reproduction in its environment.
Selection is not always of the most fit to survive.
Antarctica is a continent and krill are sea animals. The liquid sea is always warmer than the ambient temperature in Antarctica. The cold Southern Ocean is a natural habitat for krill.
By sucking people and animals blood, of course same thing they always do.
The process is called "natural selection" and is the basis of Charles Darwin's studies on evolution. Animals or plants which are better adapted for the conditions they live in (someone is always better than someone else) tend to survive longer and have more offspring. In turn (because the traits are passed on) these offspring can do as well or better than the parents in that environment and so the population becomes progressively more adapted to the conditions.
they always had to hunt animals to survive
Uncontrolled hunting, deforestation, and altering of their natural environment by humans.
You have to be strong and survive and when it rains block any water from coming in. A lot of natives in places like Africa live in huts and always have and they survive this is because they are born to survive in an environment like this.
soemtimes but not always