source: http://www.oceanlifecentre.dk

An example - life table for females: United States, 2003
National Vital Statistics Reports, Vol 54

lx - probability of surviving to age x
r - reproduction potential

An example - life table for females: United States, 2003

National Vital Statistics Reports, Vol 54

A bit more, how to calculte it:

[1] "Age of Miss World 2021 = 22"

Croft DP, Brent LJN, Franks DW, Cant MA (2015) The evolution of prolonged life after reproduction. Trends Ecol Evol 30:407–416.

Croft DP, Brent LJN, Franks DW, Cant MA (2015) The evolution of prolonged life after reproduction. Trends Ecol Evol 30:407–416.

Mother hypothesis (ADAPTIVE) - menopause was selected for humans because of the extended development period of human offspring and high costs of reproduction, so that mothers gain an advantage in reproductive fitness by redirecting their effort from new offspring with a low survival chance to existing children with a higher survival chance.

Pavard S, Metcalf CJE, Heyer E (2008) Senescence of reproduction may explain adaptive menopause in humans: A test of the “mother” hypothesis. Am J Phys Anthropol 136:194–203.

Grandmother hypothesis (ADAPTIVE) - identifies the adaptive value of extended kin networking. Since the costs of reproducing become greater with age, and energy devoted to those activities would be better spent helping the offspring in their reproductive efforts (via genetics, social networks, resource aquisition)

Lahdenperä M, Lummaa V, Helle S, et al (2004) Fitness benefits of prolonged post-reproductive lifespan in women. Nature 428:178–181

Grandmother hypothesis (ADAPTIVE): post-reproductive leaders

Croft DP, Brent LJN, Franks DW, Cant MA (2015) The evolution of prolonged life after reproduction. Trends Ecol Evol 30:407–416.

Reproductive conflict hypothesis (ADAPTIVE): Local group relatedness increases with age in female killer whales; young females are predicted to invest more in reproductive competition; the costs of co-breeding with kin are greater for old compared to young females.

Croft DP, Brent LJN, Franks DW, Cant MA (2015) The evolution of prolonged life after reproduction. Trends Ecol Evol 30:407–416.

Patriarch hypothesis (NON-ADAPTIVE)- selection pressure on male longevity extended the female lifespan; whose adjustment of life history has been constrained by the size of the ovaries – resulting in human females surviving beyond the age at which they can reproduce

Three assumptions:

*older males must reproduce

*the allele for slowing life history and extending longevity is not on the Y chromosome

*increasing the ovarian follicular reserve is difficult

Marlowe F (2000) The patriarch hypothesis. Hum Nat 11:27–42.

Patriarch hypothesis (NON-ADAPTIVE) - sparrow example - older males do reproduce, actually benefit of extra-pair fertilization and produce more sperms compared to young males

Girndt A, Cockburn G, Sánchez-Tójar A, et al (2019) Male age and its association with reproductive traits in captive and wild house sparrows. EcoEvoRxiv Prepr 1–35.

Other non adaptive hypotheses:

• artificial longevity due to medicine and protected environments

• epiphenomenon of antagonistic pleiotropy favouring early-life fertility at the expense of fertility later in life

Croft DP, Brent LJN, Franks DW, Cant MA (2015) The evolution of prolonged life after reproduction. Trends Ecol Evol 30:407–416.

Lahdenperä M, Lummaa V, Helle S, et al (2004) Fitness benefits of prolonged post-reproductive lifespan in women. Nature 428:178–181.

Marlowe F (2000) The patriarch hypothesis. Hum Nat 11:27–42.

Pavard S, Metcalf CJE, Heyer E (2008) Senescence of reproduction may explain adaptive menopause in humans: A test of the “mother” hypothesis. Am J Phys Anthropol 136:194–203.