Life History Tradeoffs

1. Life History Tradeoffs By:Tanesha L. Haynes

2. What is life history? • Life history characters involve the pattern of reproduction and death over time • Life history consist of the adaptations of an organism that influence aspects of its biology, such as…

3. The number of offspring it produces • Its survival • Its size and age at reproductive maturity • Body size

4. Lifespan/longevity • Age at first reproduction

5. Tradeoff

6. What is a tradeoff • A relationship of central importance of most biology species

7. Because all organisms have access to limited energy and other resources, there is a trade-off between the number and size of offspring • Differences among life histories concern differences in the allocation of energy

8. Whenever there is a tradeoff between different components of fitness, favor is given to individuals that allocate energy and time. • Changes in life history are caused by changes in the allocation of energy

9. How many offspring should an individual produce in a given year? • Concerned with trade offs • The more offspring a parent attempts to raise at once, the less time and energy the parent can devote to caring for each one • Clutch size

10. How big should each offspring be? • A tradeoff between size and number should be fundamental • Individuals offspring will have a better chance of survival if they are larger • As an offspring gets larger, its probability of surviving increases • The optimal size depends on the shapes of the relationships for offspring number versus size and offspring survival versus size

11. In conclusion • Because all organisms have access to limited energy and other resources, there is a tradeoff between the number and size of offspring • Those that produce larger offspring are constrained to produce fewer, while those that produce smaller offspring may produce larger numbers

12. The End