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Author (up) Lee, R.D.
Title Rethinking the evolutionary theory of aging: transfers, not births, shape senescence in social species Type Journal Article
Year 2003 Publication Proceedings of the National Academy of Sciences of the United States of America Abbreviated Journal Proc Natl Acad Sci U S A
Volume 100 Issue 16 Pages 9637-9642
Keywords Adaptation, Physiological; *Aging; Animals; *Biological Evolution; Demography; Economics; Environment; Fertility; Humans; Life Expectancy; Longevity; Models, Theoretical; Parturition; Population Dynamics; Population Growth; Reproduction
Abstract The classic evolutionary theory of aging explains why mortality rises with age: as individuals grow older, less lifetime fertility remains, so continued survival contributes less to reproductive fitness. However, successful reproduction often involves intergenerational transfers as well as fertility. In the formal theory offered here, age-specific selective pressure on mortality depends on a weighted average of remaining fertility (the classic effect) and remaining intergenerational transfers to be made to others. For species at the optimal quantity-investment tradeoff for offspring, only the transfer effect shapes mortality, explaining postreproductive survival and why juvenile mortality declines with age. It also explains the evolution of lower fertility, longer life, and increased investments in offspring.
Address Department of Demography, University of California, 2232 Piedmont Avenue, Berkeley, CA 94720-2120, USA. rlee@demog.berkeley.edu
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Language English Summary Language Original Title
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ISSN 0027-8424 ISBN Medium
Area Expedition Conference
Notes PMID:12878733 Approved no
Call Number Equine Behaviour @ team @ Serial 5465
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Author (up) Turner, A.; Kirkpatrick, J.F.
Title Effects of immunocontraception on population, longevity and body condition in wild mares (Equus caballus) Type Journal Article
Year 2002 Publication Reproduction (Cambridge, England) Supplement Abbreviated Journal Reprod Suppl
Volume 60 Issue Pages 187-195
Keywords Animals; *Animals, Wild; Antigens/administration & dosage; Body Constitution; Contraception, Immunologic/methods/*veterinary; Egg Proteins/administration & dosage; Female; *Horses; Longevity; Membrane Glycoproteins/administration & dosage; Population Control; Population Dynamics; *Receptors, Cell Surface; Swine; Vaccines, Contraceptive/administration & dosage
Abstract Contraception is becoming a common approach for the management of captive and wild ungulates yet there are few data for contraceptive effects on entire populations. Management-level treatment of mares with porcine zona pellucida (PZP) vaccine resulted in zero population growth of the Assateague Island wild horse population within 1 year of initiation of treatment. Contraceptive efficacy was 90% for mares treated twice in the first year and annually thereafter. For mares given a single initial inoculation, contraceptive efficacy was 78%. The effort required to achieve zero population growth decreased, as 95, 83 and 84% of all adult mares were treated in each of the first 3 years, compared with 59 and 52% during the last 2 years. Mortality rates for mares and foals after the initiation of management-level treatments decreased below historic and pretreatment mortality rates of approximately 5%. Two new age classes have appeared among treated animals (21-25 years and > 25 years), indicating an increase in longevity among treated animals. Body condition scores for all horses, all adult mares and non-lactating mares increased significantly between summer 1989 and autumn 1999 but did not change significantly in lactating mares. These results provide reliable data for the construction of realistic models for contraceptive management of free-roaming or captive ungulate populations.
Address Assateague Island National Seashore, Berlin, MD 21811, USA
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Language English Summary Language Original Title
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Series Volume Series Issue Edition
ISSN 1477-0415 ISBN Medium
Area Expedition Conference
Notes PMID:12220158 Approved no
Call Number refbase @ user @ Serial 142
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Author (up) Wallin, L.; Strandberg, E.; Philipsson, J.
Title Phenotypic relationship between test results of Swedish Warmblood horses as 4-year-olds and longevity Type Journal Article
Year 2001 Publication Livestock Production Science Abbreviated Journal
Volume 68 Issue 2-3 Pages 97-105
Keywords Horse; Longevity; Survival analysis; Test traits
Abstract The relationship between longevity and different traits scored in the Swedish Riding Horse Quality Test (RHQT) was studied to evaluate their use as predictors of survival. Data comprised 1815 Warmblood horses born between 1969 and 1982 that had participated in the RHQT as 4-year-olds. Survival information was obtained via a questionnaire sent to owners of horses that had participated in the RHQT between 1973 and 1986. All phenotypic values of traits scored at 4 years of age were adjusted for the effect of place/year (event). Survival analysis was performed taking into account censoring. Traits having significant effects on longevity were: conformation, legs (included in conformation), orthopaedic status, jumping ability, and the horses' combined classification score for dressage and jumping talents, respectively. Orthopaedic health had the greatest influence on longevity, and demonstrated the importance of judging health traits in young sports horses. The results of this study confirmed that there is a significant phenotypic relationship between many of the RHQT traits and longevity, and thus the possibility of using them as predictors of survival.
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Publisher Place of Publication Editor
Language Summary Language Original Title
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Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ Serial 3958
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