학술논문
Size matters: penis size, sexual maturity and their consequences for giant armadillo conservation planning
Original Article
Original Article
Document Type
Academic Journal
Author
Source
Mammalian Biology. December 2020, Vol. 100 Issue 6, p621, 10 p.
Subject
Language
English
ISSN
1616-5047
Abstract
Author(s): Camila Nascimento Luba [sup.1] [sup.2], Danilo Kluyber [sup.1] [sup.3] [sup.4], Gabriel Favero Massocato [sup.1] [sup.4] [sup.5], Nina Attias [sup.1] [sup.6], Lilja Fromme [sup.7] [sup.8], Andre Luís Rios Rodrigues [sup.2], [...]
The giant armadillo (Priodontes maximus) is the largest living armadillo and is classified as Vulnerable by the International Union for Conservation of Nature. Little is known about the species biology and especially its reproduction. However, data such as the age at sexual maturity are employed for estimation of a species generation length, which is an important parameter for extinction risk assessment. Thus, the aim of this study is to estimate the age at sexual maturity for male P. maximus in the wild and to predict generation length for this species. During a long-term in situ study, eight male P. maximus were captured for reproductive evaluation considering both morphometric characteristics (e.g. body, penis and testes dimensions), and data on sperm production (assessed by electroejaculation). Based on observations of this study, it is estimated that male P. maximus reach sexual maturity at an age of 6.5-8 years. This is at least 5.5-7 years later than previously published. Consequently, generation length for P. maximus results in 11 years when applying standard formula including age at sexual maturity in males and an estimate of age at last reproduction of 20 years. However, the generation length is probably underestimated here as sexual maturity in females and age at last reproduction could be later than estimates used. Even these conservative estimates result in noticeable change for the timeframe used in extinction risk assessments for this species as it is 33 instead of 21 years. Thus, results from this study might affect the classification status of P. maximus particularly for regional assessments.
The giant armadillo (Priodontes maximus) is the largest living armadillo and is classified as Vulnerable by the International Union for Conservation of Nature. Little is known about the species biology and especially its reproduction. However, data such as the age at sexual maturity are employed for estimation of a species generation length, which is an important parameter for extinction risk assessment. Thus, the aim of this study is to estimate the age at sexual maturity for male P. maximus in the wild and to predict generation length for this species. During a long-term in situ study, eight male P. maximus were captured for reproductive evaluation considering both morphometric characteristics (e.g. body, penis and testes dimensions), and data on sperm production (assessed by electroejaculation). Based on observations of this study, it is estimated that male P. maximus reach sexual maturity at an age of 6.5-8 years. This is at least 5.5-7 years later than previously published. Consequently, generation length for P. maximus results in 11 years when applying standard formula including age at sexual maturity in males and an estimate of age at last reproduction of 20 years. However, the generation length is probably underestimated here as sexual maturity in females and age at last reproduction could be later than estimates used. Even these conservative estimates result in noticeable change for the timeframe used in extinction risk assessments for this species as it is 33 instead of 21 years. Thus, results from this study might affect the classification status of P. maximus particularly for regional assessments.