Darwin's theory
four postulates
Variation
Darwin includes a lot of variety within every species, which makes the world have very e types of animals everywhere. Also this is why there are very different environments around the world, so every species is suited with the environment that they like the most. Variation also includes for example insects that have different colors, and that eat different things, everything has its own variation.
Inheritance
Every species offsprings looks like their parents because they inherit special traits. This is why these offsprings are able to live in the environment that their mothers had them and may be suited to the environment and their mothers help them live in it and get used to it so they can start living on their own.
Differential Survivor
This process is known as natural selection, some external conditions may affect survival on some species. These are non-genetic changes that occur in a species, things that cannot be passed down to the next generation.
Extinction
Some traits for some species are not able to live in the environment that they are put into or not suited into them so those will die. Extinction is the end of a organism or of a group of organisms, its the death of the last individual. The graph below demonstrates the amount of species that become extinct every year which are not much. But if every year we lose too by the end of the century there will be few animals left.
Sources
Genetics: The Study of Heredity. (2016).LiveScience.com. Retrieved 4 April 2016, from http://www.livescience.com/27332-genetics.html
How many species are we losing?. (2016). Wwf.panda.org. Retrieved 4 April 2016, from http://wwf.panda.org/about_our_earth/biodiversity/biodiversity/
heredity | genetics. (2015). Encyclopedia Britannica. Retrieved 4 April 2016, from http://global.britannica.com/science/heredity-genetics
Natural selection (2 of 4) Differential reproduction. (2016).Evolution.berkeley.edu. Retrieved 4 April 2016, from http://evolution.berkeley.edu/evolibrary/search/imagedetail.php?id=314&topic_id=&keywords=