13.2: Life History Trade-Offs

fecundity

organism’s reproductive capacity (number of offspring its capable of producing)

parental investment

energetic investment into egg offspring (egg/seed size. amount of parental care)

quality vs quantity trade off

higher fecundity (quantity) means lower parental investment (quality) and vice versa. e.g.:

• Atlantic cod produces millions of eggs during spawning and these eggs hatch into larvae that are immediately self-sufficient

• Humpback whales give birth to 1 calf every 2 years and each calf stays with female for up to 10 months

early reproduction strategy

short-lived and small in body size. Early energy geared towards reproduction rather than growth. reduces risk of not reproducing at all. e.g. mice

later reproduction strategy

long-lived and larger body size. Energy initially geared towards growth to lower mortality and then later in life energy for reproduction. Higher risk of not reproducing at all. e.g. elephants

how is the relationship between growth and reproduction a trade-off

both require energy - towards growth enhances survival but delay reproduction, towards reproduction compromises growth and future survivability.