Chapter 3, Problem 1PDT

Summary Introduction

To explain: The criteria or measurements for the better adaptability of the population after a certain evolutionary change.

Introduction: Adaption is a natural phenomenon and it is a distinguishing character of the organisms that are evolved by natural selection. Therefore, adaption is also an evolutionary process. Over time, organisms alter their characters to adapt to certain changes in the environment.

Explanation of Solution

Evolution is a process which results in some heritable changes in the population. These changes may be caused by many factors and one of them is natural selection. Evolution leads to the adaption of certain characters by the organism. An organism is said to be better adapted if the characters adapted after evolution are more fit than the previous generation. For example, wings of penguin are adapted to swimming in water which is a beneficial feature for penguins. Natural selection is one of the main reasons for better adaptability among the population.

For measurement of adaptability, it is important to first understand about the function of the feature that whether the feature makes the organism more fit with respect to survival and reproduction or not.

Better adaptability after evolution can be measured on the basis of efficient accomplishment of certain functions in the organism which was not possible before. After evolution, the organism becomes more fit in reproduction and survival.

Criteria or methods that explain that some organisms are better adapted after evolution are:

• Complexity:

  With evolution, the character becomes more complex to perform various functions, because the complexity of any organs is dependent on the process of natural selection. Therefore, understanding the level of complexity in various organisms can help in understanding their evolutionary pattern.

• Design:

  The design of any organ of the organism can be due to adaptation to the surrounding environment. For example, the plants living in the hot conditions, have designed their leaves in the form of leaflets as an adaptation to conserve loss of water. Therefore, understanding the design of any organ helps in understanding the evolutionary changes.

• Experiments:

  The experiments done by the organisms to change some functions of the organs helps them to adapt better as compared to the other members of the group that do not experiment. For example, various plants have shifted from bird pollination to insect pollination that helped them in surviving more as compared to others.

• Comparative method:

  It is a very significant method to compare the adaptive significance of any feature. By analyzing the evolutionary trend of a feature in previous generations, it is easy to identify the improved function of that feature. This helps in understanding the adaptability function of those organs.

Hence, evolutionary changes that increase the fitness of the organism by increasing the chances of survival and reproduction rate are important factors which explain that the population is better adapted after evolution.