Darwin's Postulates
Gabriela Guzmán
WHAT ARE THEY?
Variation - There is a lot of variety within a species
Inheritance - Offspring look like their parents
Differential Survival - External conditions can affect survival
Extinction - Some traits are not suited to survival and those with them will die out.
Inheritance - Offspring look like their parents
Differential Survival - External conditions can affect survival
Extinction - Some traits are not suited to survival and those with them will die out.
Variation
An individual organism can vary in the traits they possess for example their shape, size and color. An example can be the Bengal tiger and the Siberian tiger. They are the same species but their aspect is different.
Inheritance
This postulate states that species and organisms may inherit their traits down to their next generations giving them a very similar aspect to what they look like. For example, a very fat person may have an offspring which is probably going to have the tendency to become fat in the future.
Differential Survival
There are many organisms who go out to the real world and begin to live a life they think will survive, however, not all organisms are able to adapt to the conditions of the biome they were born in and eventually die, others, who might possess different qualities than the ones who weren't fit for the environment, are able to pass them on to other generations and help them maintain their species alive. One example of differential survival is the species in cold environments that aren't able to withhold the temperature and some of the organisms are able to do so they reproduce to create more organisms that can remain standing.
Extinction
Species have certain traits that are somehow fit for the environment they live in. Extinction comes around whenever those species aren't able to change their traits throughout evolution to be able to adapt to the environment they still appear in. For example, the polar bears, which are in danger of extinction is because they do not have their appropriate temperature for a longer time since the global warming is getting to all places on earth including the artics and is affecting the animals which need those temperatures the most.
Sources
C.V. (2015, May 13). Bengal Tigers. Retrieved April 4, 2016, from http://btiger.weebly.com/
Freeman, S., Quillin, K., Allison, L., Black, M., Podgorski, G., Monroe, J., & Taylor, E., (2014). Homeostasis, How Do Animals Regulate Body Temperature? In Biological Science (5th. Edition ed., Vol. Volume 3, pp. 853-858). Glenview, Illinois: Pearson Education.
M. S. (22, December 2014). White Seals. Retrieved April 4, 2016, from http://arabse1.blogspot.mx/2010/11/white-seals-physical-features.html
U. (2008, April 30). Polar Bears. Retrieved April 4, 2016, from https://en.wikipedia.org/wiki/Polar_bear