Reproductive isolation (1).,,,,,,,,,,,,,,,,,,,,,,,,,,,,pptx

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1. Reproductive isolation By zainab salim

2. What is Reproductive Isolation? Reproductive isolation is when two or more groups of living things (like animals or plants) can't produce fertile offspring, even if they try to mate. This happens because of differences in their genes, behavior, or physical characteristics .

3. Types of Reproductive Isolation There are two main types of reproductive isolation : 1.Prezygotic Reproductive Isolation 1.Postzygotic Reproductive Isolation

4. Prezygotic Reproductive Isolation This type of isolation happens before fertilization. It's like a "no-go" signal that prevents two different species from mating. Examples include:- Geographic isolation : Imagine two groups of birds living on different islands. They can't mate because they're separated by water . - Temporal isolation: Think of two groups of flowers that bloom at different times. They can't pollinate each other because they're not blooming at the same time .- Behavioral isolation : Picture two groups of birds with different courtship dances. They can't mate because they don't recognize each other's dances .- Mechanical isolation : Imagine two groups of insects with different-shaped genitalia. They can't mate because their bodies don't fit together.

5. Postzygotic Reproductive Isolation This type of isolation happens after fertilization. It's like a "stop" signal that prevents the development of fertile offspring. Examples include :- 1.Genetic incompatibility: Think of two groups of plants with different numbers of chromosomes. They can't produce fertile offspring because their genes don't match.- 2.Hybrid inviability : Imagine two groups of animals that produce offspring that don't survive. This happens because their genes don't work well together .- 3.Hybrid sterility: Picture two groups of animals that produce offspring that can't reproduce. This happens because their genes don't work well together.

6. How Does Reproductive Isolation Happen? Reproductive isolation can happen through different mechanisms, including:- 1.Genetic drift: Random changes in gene frequencies can lead to reproductive isolation .- 2. Natural selection: Different environmental pressures can lead to the selection of different traits, resulting in reproductive isolation .- 3. Mutation: Genetic mutations can result in reproductive isolation .- 4. Gene flow: The movement of genes from one population to another can lead to reproductive isolation .

7. Why is Reproductive Isolation Important? Reproductive isolation is crucial for the formation of new species. Without it, species wouldn't be able to adapt to their environments and evolve into new forms . Examples of Reproductive Isolation- The London Underground mosquito: This mosquito species is found only in the London Underground and can't mate with other mosquito species .- The Galapagos finches : These birds are found only on the Galapagos Islands and can't mate with other finch species.- The apple maggot fly: This fly is found only in North America and can't mate with other fly species .