Question

When an individual behaves in a way that reduces its own fitness but increases the fitness of others of its species, it is exhibiting a. kin selection. d. selfishness. b. group selection. e. ignorance. c. altruism.

Short answer

c. Altruism

Step-by-step solution

Understand the behavior described

The behavior described in the question refers to an action that decreases an individual's own fitness but increases the fitness of others in its species. This means that the individual is making a sacrifice for the benefit of others. This sacrificial behavior has a specific term in biological contexts.

Compare this behavior with each term

Now, compare this behavior with each term. a. kin selection - this refers to the evolutionary strategy that favours the reproductive success of an organism's relatives, even at a cost to the organism's own survival and reproduction. b. group selection - in biology, refers to a process where natural selection acts at the level of the group, rather than at the level of the individual. c. altruism - behavior by an individual that increases the fitness of others while decreasing its own. d. selfishness - behavior that puts the individual's fitness above others. e. ignorance - this doesn't have a specific biological context, but refers to lack of knowledge or awareness.

Identify the correct term

In this context, the behavior described aligns with the definition of altruism. This is the act of an individual causing a reduction in its fitness in favor of others' fitness. Therefore, the correct term for this behavior is c. Altruism, as it most accurately describes the behavior in the question.

Key concepts

Kin Selection

In the world of biology, kin selection plays a critical role when discussing altruistic behavior. Kin selection is an evolutionary strategy that favors the reproductive success of an organism's relatives, even when it comes at a personal cost to the individual. It is derived from the notion that genes are more likely to be preserved through family lines.

The principle behind kin selection is that individuals can pass on their genes not only through their own offspring but also by helping close relatives to reproduce. Helping relatives increases the spread of shared genetic material.

• This can be seen in actions like worker bees caring for their queen's offspring rather than reproducing themselves.
• It explains why siblings may make 'sacrifices' for each other, such as diverting resources or aiding in the care of nieces and nephews.

Kin selection reveals that the evolutionary measure of success isn't only personal reproduction, but also aiding the survival of kin that share similar genes.

Group Selection

Group selection refers to the idea that natural selection acts on groups of individuals instead of just individual organisms. This concept suggests that traits favorable to the group's success can evolve, even if they might be detrimental to the individual's direct fitness.

The idea is that a cohesive group with altruistic behaviors might out-compete another group where members act solely in self-interest.

• Traits like cooperation and hunter-gatherer societies working collectively are examples.
• Group selection explains why some behaviors that appear selfless might actually evolve because they benefit the entire group or community.

Although group selection is a more controversial concept than kin selection within evolutionary biology, it illustrates how behaviors beneficial to group survival can develop and persist, supporting the survival of the genes within the group.

Evolutionary Strategy

Evolutionary strategy encompasses the different tactics organisms adopt to ensure survival and reproduction. These strategies involve complex behaviors tailor-made to enhance an organism's fitness. Within the context of altruism, these strategies may appear to lower individual fitness but enhance genetic propagation.

Understanding evolutionary strategy helps explain the diverse methods life has developed to address challenges.

• For instance, some animals develop symbiotic relationships, where partners benefit each other's survival needs.
• Certain plants have evolved mutualistic relationships with pollinators, ensuring pollen is spread more effectively.

These strategies illustrate the complexity of evolution, highlighting how organisms adapt not only by improving individual traits but also through interactions and relationships with others, ultimately aiming to increase the propagation of shared genetics.