Question

Why do some animals live in groups, rather than alone? 1) definitions of cooperation, kin selection and altruism; 2) the benefits and costs of social living; 3) the concepts of indirect fitness and inclusive fitness, and 4) explain why some individuals forego their own reproduction in order to help their parents rear siblings.

Answer 1

Animals live in groups to get benefitted for one or more reasons such as :

A) Some animals jointly attack preys bigger than them with little efforts and risk.

B) Some animals share their hunting locations with each other to help them easily achieve food.

C) Some animals avoid getting eaten by the predator as they stay in groups and become less susceptible to attack.

D) Some animals get benefitted by getting help when it comes to taking care of the young ones.

1) Cooperation is a type of behaviour where organisms work or act together for common or mutual benefits. For example, Bulls stay, eat and move in a herd so as to prevent an attack from the predators. When attacked by the predator they form a group encircling the young ones in the centre facing outwards to protect them from attack.

Kin selection is the behaviour of animals to ensure that their genes and close genetic relatives survive.

Altruism is the behaviour performed for the benefits of others by the action of self-sacrifice.

Both kin selection and altruism are related because the kin selection is the tendency of an organism to act altruistically in the interest of their own relatives. Altruistic behaviour increases with the increase in the degree of relatedness.

2) The benefits of social living have been discussed above. The negative effects of social living include:

A) Competition for resources among the individuals if the resources are few.

B) Large groups often attract the attention of predators.

C) The presence of few resources often causes a challenge to maintain the good health of all members of the group.

3) Fitness of an organism can be subjected to its reproductive success. It has been divided into direct fitness and indirect fitness.

Inclusive fitness is the term defined for direct fitness and indirect fitness of an organism. It is the total genetic contribution of the organism to the next generation as it includes its offsprings and the number of individuals it can add to the population by supporting others.

Direct fitness is the reproductive success of the organism indicating the number of offsprings it produces during its lifetime and how many of them survive.

Indirect fitness only includes the contribution of the organism which increases the fitness of its relatives (with whom the genes are shared) and thus increases the fitness of the group.