100 plalet other smart tool-users might. It is a question we might eve able to a

Question

100 plalet other smart tool-users might. It is a question we might eve able to answer one day. Thousands of exoplanets have no discovered and even though we've yet to find any just like ours, l the evidence suggests there are plenty of Earth-like planets c enough that we might not only determine whether they support life, but also learn a little about it. The answer may be in the stars. n be w been lose Critical Thinking 1. How do the processes of random mutation and natural selection interact to bring about evolution? 2. What role does the "founder effect" have in creating new species? 3. How does "genetic drift" help to explain variations that were not selected for? 4. Discuss convergent evolution as a way of explaining similar characteristics evolving separately in different species. Internet References Understanding Evolution

Explanation / Answer

Ans (1)- "Natural selection is a process by which organism with favorable variation survive and reproduce at a high rate. This will occur The adaptation ( an inherited variation that increases an organisms chance of survival in a particular environment). "

And if random mutation will happened , the organism which are adapted for a particular random mutation will survive other will die.

SO, OVER MANY GENERATION, AN ADAPTATION COULD SPREAD THROUGHOUT THE ENTIRE SPECIES. IN THIS WAY EVOLUTION BY NATURAL SELECTION AND RANDOM MUTATION WILL OCCUR.

ANS (2)-

"a founder effect occurs when a new population (new colony) develops by a few members ( known as founder population) of the original population. "

This is essentially a sampling difference, the larger the sub-population the more likely it will resemble the original (parent ) population and the small number of individuals that act as founders might not posses all the alleles present in the parent population, and might display different frequency of those that they do possess.

The founder effect can result in radical changes in allele frequencies.

So in this a new small species will formed.

ANS (3)- Acc to genetic drift - "In finite population, random sampling can cause an existing allele to lost. This causes random change in allele frequencies."

It causes fixation of alleles. When the allele reaches a frequency of 1, it is said to be fixed ,once an allele become fixed, genetic drift comes to halt, and the allele frequency can not change unless a new allele is introduced in the population via mutation or gene flow.

THUS EVEN GENETIC DRIFT IS A RANDOM, DIRECTIONLESS PROCESS, IT ACTS TO ELIMINATE GENETIC VARIATION OVER TIME.

ANS (4) - CONVERGENT EVOLUTION- "it describes the acquisition of same biological trait in unrelated species.

Example of this is the streamlined shape of sharks and dolphins.

One is fish, and the other is a mammal, and they are related to one another in only the most distant sense. But if it's life depends on swift movement through the water, then a streamlined shape is pretty much essential.

Another example is wings in birds, bats and flies.

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.