Which best describes biogeographic isolation?

Enjoying this? There's more where that came from! Explore our full range of academic writing services designed just for you—because great work deserves the perfect partner. Flip the page and let’s make it happen!

Assignment Help Dissertation Help Homework Help Essay Writing Coursework Help

A) When two species share the same habitat but feed on different resources.

B) The separation of populations of the same species by physical barriers, leads to reproductive isolation.

C) The adaptation of species to different environmental conditions within the same ecosystem.

D) The competition between species for limited resources in the same environment.

Correct Answer:

B) The separation of populations of the same species by physical barriers, leads to reproductive isolation.

Explanation:

Biogeographic isolation refers to the separation of the same species due to physical barriers. This barrier could be mountains, rivers, deserts, and more. Such physical barriers disable the population from move from one place to another, leading to genetic divergence. In some cases, the gene pool could be affected and lead to reproductive isolation.

Why Not the Other Options?

A) When two species share the same habitat but feed on different resources

• This option defines resource partitioning instead of biogeographic isolation. Moreover, the effects of the two conditions are completely different. Resource partitioning leads to decreased competition between the people and can have positive impacts on their growth.

C) The adaptation of species to different environmental conditions within the same ecosystem.

• Species adapt to different environmental conditions within the same ecosystem in different ways. This process can be said to be natural selection or could be called ecological differentiation.

D) The competition between species for limited resources in the same environment.

• Competition between species for limited resources doesn't involve any physical barriers. They might create some, or even isolate others but that doesn't mean biogeographic isolation.

Additional Details About Biogeographic Isolation

Types of Barriers Leading to Isolation

• Geographical barriers – Mountains, rivers, and oceans.
• Environmental barriers – Climate differences, like deserts and tundras.
• Human-made barriers – Roads, cities, and deforestation.

Genetic Impact of Biogeographic Isolation

• A limited gene pool can create mutation among the existing species.
• Over time the species can become genetically distinct and create new species altogether.

Examples of Biogeographic Isolation

• Galápagos finches – Separated by islands, they evolved into different species.
• Darwin's tortoises – Different island environments led to variations in shell shape and size.
• Australian marsupials – Isolated from other continents, they evolved distinct traits.

Frequently Asked Questions

How is biogeographic isolation different from ecological isolation?

The main difference between the two lies in the type of isolation itself. Biogeographic isolation occurs when two species are separated by physical barriers. Ecological isolation occurs when species occupy different habitats in the same geographical areas leading them to isolate and prevent inbreeding.

Can human activity create biogeographic isolation?

Yes, and it happens a lot. When humans create highways, dams, or simply urban development itself, it can lead to such isolation. Many species have faced biogeographic isolation due to this and deforestation still continues to do so.

What role did biogeographic isolation play in Darwin’s theory of evolution?

Darwin’s observations of the Galápagos finches highlighted how isolation on different islands led to the development of distinct species.

Can climate change influence biogeographic isolation?

Climate change can also influence biogeographic isolation. Shifts in the climate conditions affect preexisting habitats and create new barriers. This leads to more isolating conditions.

Why are island species more susceptible to biogeographic isolation?

Island species have clear biological isolations that separate them from the others. This limits the gene flow. However, it can lead to divergence and speciation based on the different resources species choose.

How does biogeographic isolation affect genetic diversity?

The reduced genetic pool can also lead to varied genetic mutations. This has an increased chance for genetic diversity.