Life History Trade-Offs

What does life history describe?

The competitive allocation of limited resources between physiological functions

What happens under energetic stress?

Competing processes within the body will undergo a trade-off

What does a trade-off involve?

A greater allocation of resources towards one function whilst limiting the resources available to another based on the necessities of both. There is a strong selective pressure for 'energetic efficiency'

What happens during times without energetic stress?

Mediators such as testosterone can still mediate energy allocation

Is energy a limited resource?

Yes, energy is a limited resource so the body has to allocate the available energy to the process deemed most important for survival

What are some examples of trade-offs?

• The trade-off between reproduction and survival

• In many bird species, individuals that produce a large number of offspring in a single breeding season often have a reduced chance of surviving to the next season

• Testosterone in males as high testosterone levels can boost reproductive levels increasing a male's chance of mating and reproducing. Testosterone levels can also boost attractive features in males such as increased growth in height and greater muscle synthesis which can help attract mates. However, higher testosterone levels can lower immune activity within the body. This trades off reproduction rather than survival

What shows different attributes and the differences between iteroparity and semelparity species?