Summary

This video explains two of the main types of speciation. It provides examples of certain isolations or barriers that make way for a new type of species to form. It explains what environmental, or internal factors could cause a species to develop into a new species and why that development happens.

Why watch this video?

Have you ever wondered what classifies a species?

Would you like to know the factors that can cause the rise of a new species?

Have you ever been confused by how a certain species looks or acts similar to another species?

Key terms

Species: A group of individuals that can breed with each other or have the potential to breed, and that do not breed with other groups.

Hybrid: The offspring resulting in the inter-breeding of two different species. The offspring are usually infertile, preventing gene flow between the species.

Habitat Isolation: Organisms of the same species living in the same geographic location prefer different habitats or environments. An example of this would be that some lizards prefer to live mostly in water and some prefer to live on land and seldomly go into the water.

Loose ends

1. There are many other types of speciation that are not covered in the video including parapatric speciation, peripatric speciation and artificial speciation. Parapatric speciation occurs when a species is spread out over a large area, but unlike allopatric speciation, instead of the species being separated by a physical barrier, they are separated due to differences in the same environment. For example, a part of the environment could be polluted with certain minerals or chemicals. Peripatric speciation happens when a small group breaks off from a larger group and forms a new species. Physical barriers play a role in this type of speciation but unlike allopatric speciation, one group is much smaller than the other, and the unique characteristics of the smaller group make way for a new species to form through breeding. Artificial speciation is, you guessed it, the creation of a new species by humans through lab experiments.
2. The video only talks about speciation with different animal species, but speciation also happens with plants, much the same way that speciation happens with animals.
3. The video doesn’t discuss the time frame in which a new species develops. The simple answer is that it can take a couple decades or a few thousand years for a new species to develop. It all depends on if a species can self-fertilize (as bacteria and some plants can) or if it requires a male and female to produce a zygote. Speciation with a self-fertilizing species can produce a new species quicker than if a male and female are needed to reproduce because with a male and female producing a zygote, the gene pool would remain consistent. It also depends on how long an animal takes to reproduce. For example, a female rabbit’s gestation period is on average thirty days, where a female elephant stays pregnant for twenty-two months.

Self-test questions

Question 1

How does geography play a role in speciation?

Answer A: Organisms of the same species would need to develop a way to overcome the geological barrier to interbreed.

Answer B: A population of one species is geographically isolated or split in groups.

Answer C: A species learns to mate with other species because it cannot overcome the geographical barrier.

Answer D: Geography does not play a significant role in speciation.

What is the answer and why?

Answer B: Geographical barriers cause new species to form because something is preventing two individuals from the same species to mate.

Question 2 

What is an example of a post-zygotic barrier?

Answer A: Different behaviours of the same species cause a new species to form.

Answer B: One group of species prefers a sandier environment while the other prefers a wetland environment.

Answer C: The offspring from a species inter-breeding is not able to reproduce.

Answer D: Different groups of the same species prefer to breed at different times of the year, month or day.

What is the answer and why?

Answer C: A post-zygotic barrier occurs after a zygote is made. A species is defined as two individuals that are able to reproduce, and a post-zygotic barrier is when the offspring of a species cannot reproduce, is too weak, or cannot fully develop before it is born.

Question 3

What is not an example of allopatric speciation?

Answer A: A river is preventing two of the same species from interbreeding.

Answer B: Organisms from the same species that live in close proximity prefer different habitats.

Answer C: Two islands within close range, with different habitats, prevent the same species from mating with each other on each island.

Answer D: A mountain range is keeping the species from interbreeding.

What is the answer and why?

Answer B: Allopatric speciation is when a geographic barrier is separating the population of the same species. Two organisms of the same species would not be able to mate with each other because they cannot get within close proximity of each other in order to reproduce.

Question 4

What is an example of a hybrid animal?

Answer A: A labradoodle.

Answer B: An albino moose.

Answer C: A liger.

Answer D: A wolf-dog.

What is the answer and why?

Answer C: A liger is a cross between two species (a tiger and a lion) and cannot reproduce, or is infertile. A labradoodle is a breed of dog, from the same species. An albino animal can reproduce with its own species. A dog is a sub-species of a wolf and a wolf-dog, the result of a dog and a wolf mating with each other, can produce offspring.

Question 5

What is the correct definition for speciation?

Answer A: When an organism from a species develops a certain trait, unlike other organisms from the same species.

Answer B: A cosmetic appearance of an organism is genetically altered within the same species.

Answer C: The origin of a new species from a pre-existing species.

Answer D: The species lives in two separate geographical locations.

What is the answer and why?

Answer C: Speciation is the evolutionary process in which part of a population of one species, evolves to become a new species. Organisms that are part of the same species can have different behavioural or physical characteristics.