Abstract
The utilization of taste and smell in reproduction is well documented in terrestrial mammals and small aquatic vertebrates but has never been fully examined in aquatic mammals.7 The endangered Florida manatee, Trichechus manatus latirostris, is one of many marine mammals suspected of utilizing chemosensation for reproductive purposes,2,5 but nothing conclusive has been demonstrated.1,6 Due to anatomical evidence including olfactory epithelium4 and taste buds3 in addition to behavioral observations of manatees' rubbing, mouthing, and sniffing, it has been hypothesized that the manatee is capable of sensing a female in estrus.2,5
Through gross and histological examination of suspected sites of chemoreception a more thorough analysis of the manatee's anatomical capabilities is possible. To date three males: perinatal, subadult, and adult and two females: subadult and adult have been assessed using gross documentation and histological processing with haematoxylin and eosin staining. The histological examination of the mouth area and nasal passages of the manatee has corroborated the presence of taste buds and olfactory epithelium. In addition gross examination of the internal and external mouth area demonstrates the presence of potential, additional receptor sites including papillae of the soft palate and cheek. The external genitalia of females have secretory areas that may be a source of signal. Through a larger sample size and more in depth histological analysis, any differences in age and sex will be demonstrated and the chemoreceptive areas will be further characterized.
References
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