Table 1. Reproductive characteristics and maintenance costs of several small mammals and primates.
| Species | Divergence from humans (MY) | Human sequence [ortholog] identity (%)a | Weight (g)b | Gestation period (mo) | Age of sexual maturity (mo) | Litter size (no.) | Typical [max] life span (yr)c | Cost per generation ($)d |
|---|---|---|---|---|---|---|---|---|
| Nonprimate small mammals | ||||||||
| Mouse (M. musculus) | 90–110 | 84 [74] | 25 | 0.7 | 1.5 | 8–12 | 2 [4] | 100 |
| Rat (Rattus norvegicus) | 90–110 | 84 [74] | 350 | 0.8 | 2 | 6–14 | 3 [4] | 300 |
| Northern tree shrew (T. belangeri) | 80–105 | 88 [71] | 150 | 1.5 | 4 | 1–5 | ND [11] | ND |
| Primates | ||||||||
| Madame Berthe’s mouse lemur (M. berthae) | 60–75 | 91 [86] | 30 | 2.1 | 8 | 1–4 | 7 [18] | 500 |
| Brown mouse lemur (M. rufus) | | | | | 40 | | | | | | | | | | |
| Gray mouse lemur (M. murinus) | | | | | 60 | | | | | | | | | | |
| Bush baby (G. demidovii) | 60–75 | 89 [85] | 60 | 3.7 | 9 | 1–2 | ND [13] | ND |
| Spectral tarsier (Tarsius spectrum) | 55–65 | 90 [77] | 120 | 6.5 | 17 | 1 | ND [12] | ND |
| Pygmy marmoset (C. pygmaea) | 30–45 | ND | 120 | 4.6 | 16 | 1–2 | ND [18] | ND |
| Common marmoset (C. jacchus) | 30–45 | 95 [89] | 300 | 4.8 | 16 | 1–3 | 8 [16] | 5,000 |
| Rhesus macaque (M. mulatta) | 20–30 | 97 [94] | 8,000 | 5.5 | 36 | 1 | 26 [42] | 20,000 |
| Chimpanzee (Pan troglodytes) | 5–8 | 99 [98] | 50,000 | 7.6 | 120 | 1 | 50 [80] | 250,000 |
| Human (Homo sapiens) | — | — | 70,000 | 9.3 | 156 | 1 | 80 [122] | 230,000 |
The Staff of the Jackson Laboratory 1966; Nowak 1999; Townsend 2001; Wrogemann et al. 2001; Glazko and Nei 2003; Tardif et al. 2003; Andrade et al. 2004; Suckow et al. 2006; Gursky 2007; Chatterjee et al. 2009; Fuchs and Corbach-Sohle 2010; Fischer and Austad 2011; Languille et al. 2012; Fan et al. 2013; Rowe and Myers 2016; Ensembl release 88 2017; Human Ageing Genomic Resources 2017; Lino et al. 2017.
Percent DNA sequence identity to human orthologous exon sequences. Brackets, percent of exon sequences with identified human ortholog. Species used for comparison: mouse lemur (M. murinus), galago (Otolemur garnettii), tarsier (T. syrichta).
Average weight of adult male in the wild.
75th percentile for age of mortality in captivity. Brackets, oldest recorded age in captivity.
Generation time (gestation period plus age of sexual maturity in days) multiplied by the 2016 per diem laboratory maintenance rates from National Institutes of Health, Division of Veterinary Resources (https://www.ors.od.nih.gov/sr/dvr/documents/dvrrates.pdf). Mouse lemur value from MHNH colony. Chimpanzee per diem rate from 2015. Human value from 2015 United States Department of Agriculture estimate of child expenditures from birth through age 17.