No description available.

Fiddler crabs are well-known for their visual displays in courtship and social interactions. However, the ability of these animals to produce and respond to chemical stimuli remains unknown. The current study investigated the existence of these cues and the information they may contain. Experiments were designed to discover any behavioral differences among populations as well as the duration of the cues. Both male and female crabs were found to be able to distinguish the size and sex of another fiddler crab by chemical cues alone, and displayed preferences for sand exposed to females and smaller crabs. Mate choice trials were conducted using crabs from a local and non-local population to determine whether these chemical cues differ among populations. Females showed a preference for males from a non-local population based on chemical cues. Larval development was studied to ascertain the duration of the planktonic larval phase as well as gain information regarding survival and development rates correlated with factors such as mother size, hatch date, and hatch size. Larval survival and duration were found to be impacted by the timing of release and the size of the mother. Population genetic analyses using cytochrome oxidase I were conducted to discover the relatedness of different populations of fiddler crabs throughout the Gulf of Mexico. Populations from Texas showed high relatedness, which may indicate high gene flow among populations.

As solitary animals, giant pandas (Ailuropoda melanoleuca) rely on chemical communication in order to determine reproductive condition of conspecifics. Therefore, we hypothesize certain biogenic volatile compounds affect mating behavior in giant pandas. Giant pandas housed at Memphis Zoo, Zoo Atlanta, San Diego Zoo, Edinburgh Zoo, and Toronto Zoo (n=5 males and n=5 females) were the subjects of this study. Urine, anatomical site, and environmental samples were collected during the breeding period (Feb-June) and non-breeding period (Aug-Dec) from 2012-2016. Volatile compounds in urine and the environment were extracted using solid phase micro-extraction (SPME), while compounds collected from various body sites of giant pandas were extracted with hexane. Compounds were analyzed and identified using gas chromatography mass spectrometry (GC-MS). Male behavioral trials consisted of a simultaneous choice test between days of the estrous cycle (e.g. proestrus, estrus, and metestrus) and pooled diestrus urine of unknown female giant pandas. The experimental period included eight 15-minute behavior trials over the course of 12 days. In addition, male giant pandas were exposed to isolated compounds found naturally in female urine during four 15-minute behavior trials over the course of 7 days. We predict that urine from a specific day of the peri-estrual period motivates sexual behaviors and physiological responses in males. Male physiological responses to female urine and specific chemical compounds were examined by changes in urinary androgen metabolites and the urinary volatile profile. By coupling male behavior responses and the female urinary chemical profile during the peri-estrual period, relevant compounds may be identified as possible pheromones related to estrus and mating behavior. To increase genetic viability of small populations, giant pandas require continued conservation and management aimed at facilitating communication and breeding across isolated populations. With low population numbers of giant pandas in the wild spread across fragmented habitats, a better knowledge of chemical communication in this species may provide vital information to improve the conservation and management of giant pandas.

Amphibian populations are in mass decline on a global scale. Various explanations have been considered, including harmful effects from exposure to toxicants. Using Xenopus laevis adults and tadpoles, potential sublethal effects of atrazine, a herbicide, were investigated in this thesis. I also investigated the toxicity of an organic herbicide compared this with the toxicity of a synthetic herbicide, using LC50 values. Whether X. laevis adult frogs could communicate chemically was tested experimentally. The results suggest that adult female X. laevis communicate chemically, but there was no evidence that male individuals did so. For testing tadpoles I used a kin-preference assay. An encouraging trend for kin preference was evident, for both an outbred and an inbred line. Tadpoles changed their behaviour after exposure to l0μg/L of atrazine for 24 hr. Kin preferences in the control tests were reversed after exposure. A hypothesis of altruistic kin avoidance was suggested by these results. However, when individuals were isolated and then exposed, these individuals had more pronounced preference for kin compared to controls. X. laevis tadpoles exposed to Organic Interceptor (organic herbicide) had a LC50 that was more than 7000 times lower than the 20% recommended dose, whereas Roundup Renews' (a synthetic herbicide) LC50 was around 8 times lower than the 1% recommended dose. This research adds to evidence that toxicants have a negative impact on amphibian populations, and suggests that more research needs to be conducted to identify other sublethal effects of toxicants and to clarify the implications these effects might have for the amphibian populations in nature.

Amphibian populations are in mass decline on a global scale. Various explanations have been considered, including harmful effects from exposure to toxicants. Using Xenopus laevis adults and tadpoles, potential sublethal effects of atrazine, a herbicide, were investigated in this thesis. I also investigated the toxicity of an organic herbicide compared this with the toxicity of a synthetic herbicide, using LC50 values. Whether X. laevis adult frogs could communicate chemically was tested experimentally. The results suggest that adult female X. laevis communicate chemically, but there was no evidence that male individuals did so. For testing tadpoles I used a kin-preference assay. An encouraging trend for kin preference was evident, for both an outbred and an inbred line. Tadpoles changed their behaviour after exposure to l0μg/L of atrazine for 24 hr. Kin preferences in the control tests were reversed after exposure. A hypothesis of altruistic kin avoidance was suggested by these results. However, when individuals were isolated and then exposed, these individuals had more pronounced preference for kin compared to controls. X. laevis tadpoles exposed to Organic Interceptor (organic herbicide) had a LC50 that was more than 7000 times lower than the 20% recommended dose, whereas Roundup Renews' (a synthetic herbicide) LC50 was around 8 times lower than the 1% recommended dose. This research adds to evidence that toxicants have a negative impact on amphibian populations, and suggests that more research needs to be conducted to identify other sublethal effects of toxicants and to clarify the implications these effects might have for the amphibian populations in nature.

No description available.

Embora os Squamata representem um grupo bastante diverso, pouco se conhece sobre sua biologia reprodutiva e caracterização química de secreções glandulares e cloacais, principalmente no que se diz respeito à fauna neotropical. A família Gymnophthalmidae reúne lagartos neotropicais, pequenos e com ampla diversidade morfológica e de habitats. Apesar de serem alvos de estudos moleculares recentes, o conhecimento acerca de sua biologia reprodutiva e composição química de feromônios é praticamente nulo em especial para as espécies serpentiformes. Calyptommatus leiolepis, Nothobachia ablephara e Procellosaurinus tetradactylus são gimnoftalmídeos simpátricos para os quais não há dados reprodutivos e químicos. Foram analisados 388 indivíduos de C. leiolepis, 180 de N. ablephara e 47 de P. tetradactylus do campo de dunas de Alagoado, Bahia. As três espécies apresentaram reprodução bastante prolongada, possivelmente contínua. Apenas machos de C. leiolepis apresentaram variação mensal no volume testicular com menores volumes entre agosto e dezembro, porém foi detectada produção de espermatozoides dentro deste período. Cópula e fertilização ocorrem simultaneamente. Todas as desovas apresentaram número fixo de 2 ovos e não há correlação entre número ou tamanho dos ovos com o CRC das fêmeas para as três espécies. Há evidências de múltiplas desovas apenas em C. leiolepis. O período de incubação das três espécies é relativamente curto e a maturação é precoce, ocorrendo provavelmente no primeiro ano de vida. As condições ambientais de temperatura e umidade relativa do ar não são restritivas ao ciclo reprodutivo, mas estão relacionadas com os picos reprodutivos das fêmeas de C. leiolepis e N. ablephara. Fêmeas são maiores do que os machos e não há dimorfismo sexual para a forma da cabeça. Entre os compostos químicos detectados em secreções de machos e fêmeas de C. leiolepis e N. ablephara há alcanos e derivados, ácidos graxos e derivados, um esteroide e diversos compostos não identificados. As principais diferenças intra e interespecíficas estão relacionadas com a porcentagem relativa dos compostos. Os ácidos graxos encontram-se em sua forma éster, típica de espécies de climas quentes e secos. / Squamata represents a very diverse group but little is known about their reproductive biology and chemical characterization of glandular and cloacal secretions, particularly concerning the Neotropical fauna. Gymnophthalmidae is a Neotropical family that comprises small to medium-sized lizards (microteiids) and shows a huge diversity of morphologies and habitats. Although targeted by recent molecular studies the knowledge of their reproductive biology and pheromone characterization is poorly known, especially for fossorial species. Calyptommatus leiolepis, Nothobachia ablephara and Procellosaurinus tetradactylus are sympatric and there are no data about their reproductive strategies and chemical composition of cloacal and glandular secretions. Gonads of 388 specimens of C. leiolepis, 180 specimens of N. ablephara and 47 specimens of P. tetradactylus from Alagoado sand dune, Bahia were analyzed. The three species showed a very extended reproduction, possibly continuous. Variation of testis volume was observed only in males of C. leiolepis with lower values between August and December but sperm production was detected within this period. Clutch size always comprised two eggs and there is no correlation between the number or size of the eggs with female SVL. Only female of C. leiolepis showed evidence of more than one clutch per year. The incubation period of the three species is relatively short and early maturation is likely occurring in the first year of life. The environmental conditions of temperature and relative humidity are not restrictive to reproductive activity, but are related to the reproductive peaks of females of C. leiolepis and N. ablephara. Females are larger than males and there is no sexual dimorphism in head shape. Among the chemical compounds detected in secretions of male and female of C. leiolepis and N. ablephara there are alkanes and derivatives, fatty acids and derivatives, a steroid and several unidentified compounds. The intra and interspecifics differences are mostly related to the relative percentages of the compounds. Fatty acids are found in its ester form, typical of species that lives in hot and dry climates.

Embora os Squamata representem um grupo bastante diverso, pouco se conhece sobre sua biologia reprodutiva e caracterização química de secreções glandulares e cloacais, principalmente no que se diz respeito à fauna neotropical. A família Gymnophthalmidae reúne lagartos neotropicais, pequenos e com ampla diversidade morfológica e de habitats. Apesar de serem alvos de estudos moleculares recentes, o conhecimento acerca de sua biologia reprodutiva e composição química de feromônios é praticamente nulo em especial para as espécies serpentiformes. Calyptommatus leiolepis, Nothobachia ablephara e Procellosaurinus tetradactylus são gimnoftalmídeos simpátricos para os quais não há dados reprodutivos e químicos. Foram analisados 388 indivíduos de C. leiolepis, 180 de N. ablephara e 47 de P. tetradactylus do campo de dunas de Alagoado, Bahia. As três espécies apresentaram reprodução bastante prolongada, possivelmente contínua. Apenas machos de C. leiolepis apresentaram variação mensal no volume testicular com menores volumes entre agosto e dezembro, porém foi detectada produção de espermatozoides dentro deste período. Cópula e fertilização ocorrem simultaneamente. Todas as desovas apresentaram número fixo de 2 ovos e não há correlação entre número ou tamanho dos ovos com o CRC das fêmeas para as três espécies. Há evidências de múltiplas desovas apenas em C. leiolepis. O período de incubação das três espécies é relativamente curto e a maturação é precoce, ocorrendo provavelmente no primeiro ano de vida. As condições ambientais de temperatura e umidade relativa do ar não são restritivas ao ciclo reprodutivo, mas estão relacionadas com os picos reprodutivos das fêmeas de C. leiolepis e N. ablephara. Fêmeas são maiores do que os machos e não há dimorfismo sexual para a forma da cabeça. Entre os compostos químicos detectados em secreções de machos e fêmeas de C. leiolepis e N. ablephara há alcanos e derivados, ácidos graxos e derivados, um esteroide e diversos compostos não identificados. As principais diferenças intra e interespecíficas estão relacionadas com a porcentagem relativa dos compostos. Os ácidos graxos encontram-se em sua forma éster, típica de espécies de climas quentes e secos. / Squamata represents a very diverse group but little is known about their reproductive biology and chemical characterization of glandular and cloacal secretions, particularly concerning the Neotropical fauna. Gymnophthalmidae is a Neotropical family that comprises small to medium-sized lizards (microteiids) and shows a huge diversity of morphologies and habitats. Although targeted by recent molecular studies the knowledge of their reproductive biology and pheromone characterization is poorly known, especially for fossorial species. Calyptommatus leiolepis, Nothobachia ablephara and Procellosaurinus tetradactylus are sympatric and there are no data about their reproductive strategies and chemical composition of cloacal and glandular secretions. Gonads of 388 specimens of C. leiolepis, 180 specimens of N. ablephara and 47 specimens of P. tetradactylus from Alagoado sand dune, Bahia were analyzed. The three species showed a very extended reproduction, possibly continuous. Variation of testis volume was observed only in males of C. leiolepis with lower values between August and December but sperm production was detected within this period. Clutch size always comprised two eggs and there is no correlation between the number or size of the eggs with female SVL. Only female of C. leiolepis showed evidence of more than one clutch per year. The incubation period of the three species is relatively short and early maturation is likely occurring in the first year of life. The environmental conditions of temperature and relative humidity are not restrictive to reproductive activity, but are related to the reproductive peaks of females of C. leiolepis and N. ablephara. Females are larger than males and there is no sexual dimorphism in head shape. Among the chemical compounds detected in secretions of male and female of C. leiolepis and N. ablephara there are alkanes and derivatives, fatty acids and derivatives, a steroid and several unidentified compounds. The intra and interspecifics differences are mostly related to the relative percentages of the compounds. Fatty acids are found in its ester form, typical of species that lives in hot and dry climates.

Proteins from the lipocalin family play significant roles during the transport of chemical signals. These globular proteins (molecular mass: 17,7 - 21,7 kDa) are able to bind a wide spectrum of volatile ligands. Since they decay continuously, the scent impact is prolonged. Major urinary proteins (MUPs) are lipocalins, typically found in the urine and used during olfactory communication in the house mouse. But the urine is not the only source of chemical signals. Many species of mammals perform selfgrooming - a technique in which saliva is transported into the fur. The goal of the thesis is to identify main proteins that are involved in chemical communication by selected species of the genus Apodemus, and to discover the source of production (i.e. saliva or urine). The Experion capillary electrophoresis system was used to confirm the absence of lipocalins in the urine in two Apodemus species (A. uralensis, A. sylvaticus). Furthermore, a lot of lipocalins is present in the saliva of above-mentioned species. The quantity and types of salivary lipocalins was identified by 2D electrophoresis along with mass spectrometry analyses (MALDI MS/MS) in three species of the genus Apodemus (A. uralensis, A. sylvaticus and A. flavicollis). The conclusion of this inter-specific comparison suggests, that sociality...

No description available.