Species Selection in Comparative Studies of Aging and Antiaging Research

An Analysis of the Relationship Between Metabolism, Developmental Schedules, and Longevity Using Phylogenetic Independent Contrasts

“…Like t max , MRDT values are not perfect measurements of the pace of aging at a physiological level but have been argued to be more accurate than t max (4,11,28). Although the debate regarding which parameter, t max or MRDT, is a better measurement of physiological aging rates has not been settled (3), MRDT values were used to provide an additional measurement of aging rates and to further strengthen our analyses.…”

“…Identifying the genetic mechanisms that regulate the pace of aging across species is a top priority in gerontology with possibly many biomedical applications (1)(2)(3). Despite their great potential as a tool for gerontological research, however, comparative studies of aging are still riddled by a few methodological problems.…”

“…Despite their great potential as a tool for gerontological research, however, comparative studies of aging are still riddled by a few methodological problems. At present, there is no accurate method to determine rate of aging for a given species, and so longevity-which, unless otherwise stated, herein refers to maximum longevity (tmax ), also called maximum life spanis usually used as an approximation (3). Indeed, numerous experiments have been carried out attempting to correlate some parameter under study with the longevity of different species (4), yet the use of simple correlations between some factor and t max , although potentially informative, may lead to further problems (5).…”

Analyses of human–chimpanzee orthologous gene pairs to explore evolutionary hypotheses of aging

“…Rhesus monkeys (Macaca mulatta), a species of Old World monkeys that diverged from apes about 25 million years ago, live up to 40 years and their onset of aging occurs at considerably earlier ages than in humans or chimpanzees; mice (Mus musculus) and rats (Rattus norvegicus), rodents that diverged from primates roughly 80 million years ago, live less than 5 years and age considerably faster than primates (Finch, 1990;de Magalhaes, 2006). To serve as an additional test, human-rhesus, human-mouse, and human-rat homolog gene pairs were downloaded from ENSEMBL v.37 (Birney et al, 2006).…”

“…Humans are longerlived than chimpanzees, with a record longevity of 122 years compared to 74 years in chimpanzees, albeit the vastly larger sample size for humans may overestimate the difference between the two species. Importantly, humans appear to feature a delayed onset of several age-related diseases and a later acceleration of mortality, a common characteristic of aging (Finch, 1990;Hill et al, 2001;Erwin et al, 2002;Morbeck et al, 2002;Finch and Stanford, 2004;de Magalhaes, 2006). Such differences in aging might be explained by changes in extrinsic mortality rates during the evolution of hominins (herein used to refer to the lineage leading to modern humans whereas hominids refers to humans and the great apes) that possibly affect selection on the pathways that govern aging (Kirkwood and Austad, 2000).…”