The biology of senescence (1956) (19759926624)

Title: The biology of senescence
Identifier: biologyofsenesce00comf (find matches)
Year: 1956 (1950s)
Authors: Comfort, Alex, 1920-
Subjects: Old age; Aging; Longevity
Publisher: New York, Rinehart
Contributing Library: MBLWHOI Library
Digitizing Sponsor: MBLWHOI Library



Text Appearing Before Image:
The Distribution of Senescence 1940, Fig. 30), in wild voles (Hinton, 1925, 1926; Elton, 1942) and in Peromyscus (Burt, 1940) senescence is never observed, judging from the state of the teeth and bones of recent and fossil animals. In some populations the vole must be regarded as an annual (Elton, 1942). Tooth wear is a reliable index of age in short-tailed shrews, those over 2 years of age being edentulous,
Text Appearing After Image:
0 8 16 24 32 40 48 56 64 72 80 88 96 Fig. 30.—Smoothed survival curve for the vole, Microtus agrestis in captivity (from Leslie and Ranson, 1940). but age limitation by this mechanical form of senescence is more potential than actual since few survive to exhibit it. They may survive in captivity up to 33 months (Pearson, 1945). The log-linear pattern of decline in survivorship is highly characteristic of birds. It has been demonstrated in the black- bird, song-thrush, robin, starling and lapwing (Lack, 1943a, b, c), redstart (Buxton, 1950), American robin (Farner, 1945) and herring gull (Marshall, 1947). In a series of robins ringed by Lack (1943a), 111 out of 144 leaving the nest (77 per cent) died 109