Speciation
Chapter Name : Heredity And Evolution |
Sub Topic Code : 103_10_09_04_01 |
Topic Name : Speciation |
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Sub Topic Name : Speciation |
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Introduction
We have seen natural selection and genetic drift within the same species, but how are new species formed?
Pre-Requisites:
Acquired and inherited traits.
Activity:
Put some red beetles and some green in green bushes near your house or school. Observe for few weeks to months and number their population. Which of these survive and produce more numbers? Natural selection and genetic drift.
Real Life Question:
If there are green beetles and red beetles in a bush, how do we know if they are two sub-populations of the same species or are of different species?
Key Words / FlashCards
| Key Words | Definitions (pref. in our own words) |
|---|---|
| Sub-population Natural Selection Genetic Drift | Different groups of organisms of the same species. When a variation becomes common since it gave a survival advantage, the variation is said to be naturally selected. Change in frequency of a variation, which provides diversity without adaptations. |
Learning aids / Gadgets
| Gadgets | How it can be used |
|---|---|
| Magnifying glass | Observe small organisms like beetles. |
Places to visit :
Garden
Practical examples around us
| Examples | Explainations |
|---|---|
| Brown bears and polar bears cannot reproduce with each other since they are of different species. |
What you learn in Theory:
Through elongated natural selection and genetic drift, new species are formed.
What you learn in Practice:
It takes a lot of time to form new species.