1.11 - Animal Reproductive Behaviours - notes

What animal reproductive behaviours are

Animals show certain patterns of actions that help them reproduce. These actions, called behaviours, are natural ways animals act to have offspring and make sure those offspring survive. Such behaviours are important because they help animals pass on their genes to the next generation.

Reproductive behaviours include actions like building nests, grouping together in herds, performing special displays during mating season, and making specific sounds or calls. Each of these helps in different ways, either by keeping young animals safe or by finding a suitable partner for reproduction.

The concept of reproductive success

Reproductive success means how well an animal can produce offspring that survive long enough to reproduce themselves. It measures an animal's ability to continue its family line. High reproductive success happens when more young survive and grow up healthy.

Animals with effective behaviours often have better reproductive success. This is because their actions directly improve the chances of finding mates or protecting their young from harm. Without these behaviours, fewer offspring might survive, leading to lower success.

Behaviours that protect young

Some reproductive behaviours focus on keeping offspring safe after they are born. These actions create a secure environment that shields young animals from predators, harsh weather, or other dangers. As a result, more young survive to adulthood, increasing the parents' reproductive success.

Nest building

Nest building involves animals creating safe shelters for their eggs or young. Birds, for example, gather materials like twigs and leaves to build nests in trees or on the ground.

How nest building protects young and improves reproductive success:

• The nest hides eggs or babies from predators and provides warmth and protection from the elements.
• This behaviour leads to more young surviving, which means higher reproductive success for the parents.

Herding

Herding is when animals group together in large numbers for safety. Many mammals, like deer or elephants, stay in herds especially when raising young.

How herding protects young and improves reproductive success:

• In a herd, adults can watch for dangers and defend the group, making it harder for predators to attack a single young animal.
• Herding reduces the loss of young to predators, resulting in more offspring reaching maturity and improving reproductive success.

Behaviours that attract mates

Other reproductive behaviours help animals find and choose partners for mating. These actions make an animal more appealing to potential mates, increasing the chances of successful reproduction. Effective mate attraction leads to more opportunities to produce offspring.

Courtship displays

Courtship displays are special movements or shows that animals perform to impress a mate. Peacocks, for instance, spread their colorful tail feathers in a fan shape.

How courtship displays attract mates and improve reproductive success:

• The display shows off strength or good health, making the animal more desirable to a potential partner.
• Successful displays lead to mating, which produces offspring and boosts reproductive success.

Calls

Calls are sounds animals make to signal to potential mates. Frogs or birds often use specific calls during breeding seasons.

How calls attract mates and improve reproductive success:

• The calls communicate location, readiness to mate, or quality as a partner, drawing in suitable mates from afar.
• Effective calls result in more mating pairs forming, leading to greater numbers of offspring and higher reproductive success.

How these behaviours connect to reproductive outcomes

Animal reproductive behaviours directly link to better outcomes by either safeguarding young or ensuring successful mating. When animals build nests or herd, they protect their offspring, which means more young live long enough to reproduce later. Behaviours like courtship displays and calls help in attracting mates, leading to the production of healthy offspring.

Overall, these behaviours work together to increase reproductive success. Animals that perform them well have more surviving offspring, continuing their genetic line. This connection shows why such behaviours are common in nature, as they give animals an advantage in reproduction.