Friday, February 21, 2020

Why do endangered species exist?

Endangered Species


“An endangered species is a type of organism that is threatened by extinction. Species become endangered for two main reasons: loss of habitat and loss of genetic variation.”


It starts with the loss of the species’ natural habitat, that include factors such as the climate being hot and dry, pollution, development for housing, industry and agriculture. As an example for this we can take the existence of dinasours, the asteroid coming to them caused the debris to enter to the atmosphere in a forced way. Making their habitat cooler, thing that they were not adapted to. It led them to be endangered and then to be extinct.

Humans nowadays are a big contribution to the damaging of various habitats, as mentioned before, with development. It has led to the complete elimination of certain habitats, an example the Amazon rainforest of South America, where they have been “clearing” the land, or thousands and thousands of acres. By “cleaning” they refer to eliminating every tree, flower, plant and any vegetation you may find. 

Development may also affect not only directly but indirectly
as well, like the destroying of trees. Trees are a habitat to many animals, and they all get cut off, more species get left out. Examples: Tree crowns provide habitat in the canopy, or top layer, of a rainforest. Plants such as vines, fungi such as mushrooms, and insects such as butterflies live in the rain forest canopy. So do hundreds of species of tropical birds and mammals such as monkeys.

Species have less room to live and reproduce.


What happens everytime loss of species’ habitats increase? 

It increases the probabilities for wild species to run into people. And as people get deeper into a species range, they are being more exposed with wild species. Not only animals, but plants that are poisonous such as fungi can grow closer to urban places. 

Polar bears, mountain lions, and alligators are all predators brought into close contact with people as they lose their habitat to homes, farms, and businesses. As people kill these wild animals, through pesticides, accidents such as collisions with cars, or hunting, native species may become endangered.


Loss of Genetic Variation: 

“Genetic variation is the diversity found within a species. It’s why human beings may have blond, red, brown, or black hair. Genetic variation allows species to adapt to changes in the environment. Usually, the greater the population of a species, the greater its genetic variation. “


The term "inbreeding" exists, and it is when species that are close family members try to reproduce and they don’t create new genetic information to be introduced to the group. 


Loss of genetic variation can occur naturally. Cheetahs are a threatened species native to Africa and Asia. 

Example: These big cats have very little genetic variation. Biologists say that during the last ice age, cheetahs went through a long period of inbreeding. As a result, there are very few genetic differences between cheetahs.


In conclusion, the conservation of endangered species is
important for humans as well. A well-balanced ecosystem purifies the environment, giving us clean air to breathe, a healthy water system to support diverse marine life, and arable land for agricultural production. When ecosystems fail, our own health is at risk.

By Katy Simmonds Campbell, Step 9