Selecting a good mate is a decision with importantfitness consequences.For this reason,mate choice has promotedthe evolution of sexual ornaments signaling the quality of an individual.In fossorial animals,inhabiting vi...Selecting a good mate is a decision with importantfitness consequences.For this reason,mate choice has promotedthe evolution of sexual ornaments signaling the quality of an individual.In fossorial animals,inhabiting visuallyrestricted underground environments,chemical senses should be very important for mate choice.We examinedwhether sexual chemical signals(substrate scent marks)produced by males of the Iberian worm lizard,Blanuscinereus,a strictly fossorial blind amphisbaenian,provide information to females on morphological traits andhealth state.We administered corticosterone(CORT)to males simulating a continuous stressor affecting theirhealth.Females preferred settling at sites scent-marked by males in comparison with similar sites with femalescent or unmarked sites,but the attractiveness of males’scent differed between individuals.Females preferredscent marks of larger/older males and with a higher immune response,while their body condition and CORTtreatment were unrelated to female preferences.Chemical analyses showed that proportions of some compounds inprecloacal secretions of males(used to produce scent marks)were correlated with the morphological(body size)and health state(immune response and body condition,but not CORT treatment)of these males.These resultssuggest that females may make site-selection decisions based on assessing the chemical characteristics of males’scent marks,which were reliably related to some of the traits of the male that produced the scent.Therefore,femalesmight use chemical senses to increase the opportunities tofind and mate with males of high quality,coping withthe restrictions of the subterranean environment.展开更多
Arid climates are characterized by a summer drought period to which animals seem adapted.However,in some years,the drought can extend for unusually longer periods.Examining the effects of these current extreme weather...Arid climates are characterized by a summer drought period to which animals seem adapted.However,in some years,the drought can extend for unusually longer periods.Examining the effects of these current extreme weather events on biodiversity can help to understand the effects of climate change,as models predict an increase in drought severity.Here,we examined the effects of“unusual”extended drought on soil invertebrate prey availability and on diet composition(based on fecal contents)and diet selection of a fossorial amphisbaenian,the checkerboard worm lizard Trogonophis wiegmanni.Weather data show interannual variations in summer drought duration.The abundance and diversity of soil invertebrates in spring were high,and similar to those found in a“normal”early autumn,after some rain had ended with the summer drought.In contrast,in years with“unusual”extended drought,abundance,and diversity of soil invertebrates in early autumn were very low.Also,there were seasonal changes in amphisbaenians’diet;in autumn with drought,prey diversity,and niche breadth decreased with respect to spring and autumns after some rain had fallen.Amphisbaenians did not eat prey at random in any season,but made some changes in prey selection that may result from drought-related restrictions in prey availability.Finally,in spite that amphisbaenians showed some feeding flexibility,their body condition was lower in autumn than in spring,and much lower in autumn with drought.If extended drought became the norm in the future,amphisbaenians might suffer important negative effects for their health state.展开更多
Melanin is the basis of coloration in many animals,and although it is often used in communication,thermoregulation,or camouflage,melanin has many other physiological functions.For example,in polluted habitats,melanin ...Melanin is the basis of coloration in many animals,and although it is often used in communication,thermoregulation,or camouflage,melanin has many other physiological functions.For example,in polluted habitats,melanin can have a detoxifying function.Melanic coloration would help to sequester in the skin the heavy metal contaminants from inside the body,which will be expelled to the exterior when the skin is sloughed.Moreover,animals should have evolved more melanic colorations in more polluted habitats(“industrial melanism”hypothesis).We examined whether the fossorial amphisbaenian reptile,Trogonophis wiegmanni,is able to eliminate heavy metals,derived from soil pollution by seagull depositions,through sloughing its skin.Our results suggest a covariation between levels of soil pollution by heavy metals and the concentration of heavy metals in the sloughed skins of amphisbaenians.This suggests that amphisbaenians may expel heavy metals from their bodies when they slough the skins.We also tested whether amphisbaenians inhabiting soils with higher levels of heavy metal pollution had darker(melanin-dependent)body colorations.However,contrary to predictions from the“industrial melanization”hypothesis,we found a negative relationship between soil pollution and proportions of melanic coloration.This contradictory result could,however,be explained because heavy metals have endocrine disruption effects that increase physiological stress,and higher stress levels could result in decreased melanogenesis.We suggest that although amphisbaenians might have some detoxifying mechanism linked to melanin in the skin,this process might be negatively affected by stress and result ineffective under conditions of high soil pollution.展开更多
基金supported by the Spanish Ministerio de Ciencia,Innovación y Universidades grant PGC2018-093592-B-I00(MCIU/AEI/FEDER,UE)by the Ministerio de Ciencia e Innovación grant PID2021-122358NB-I00(MCIN/AEI/10.13039/501100011033 and ERDF A way of making Europe).
文摘Selecting a good mate is a decision with importantfitness consequences.For this reason,mate choice has promotedthe evolution of sexual ornaments signaling the quality of an individual.In fossorial animals,inhabiting visuallyrestricted underground environments,chemical senses should be very important for mate choice.We examinedwhether sexual chemical signals(substrate scent marks)produced by males of the Iberian worm lizard,Blanuscinereus,a strictly fossorial blind amphisbaenian,provide information to females on morphological traits andhealth state.We administered corticosterone(CORT)to males simulating a continuous stressor affecting theirhealth.Females preferred settling at sites scent-marked by males in comparison with similar sites with femalescent or unmarked sites,but the attractiveness of males’scent differed between individuals.Females preferredscent marks of larger/older males and with a higher immune response,while their body condition and CORTtreatment were unrelated to female preferences.Chemical analyses showed that proportions of some compounds inprecloacal secretions of males(used to produce scent marks)were correlated with the morphological(body size)and health state(immune response and body condition,but not CORT treatment)of these males.These resultssuggest that females may make site-selection decisions based on assessing the chemical characteristics of males’scent marks,which were reliably related to some of the traits of the male that produced the scent.Therefore,femalesmight use chemical senses to increase the opportunities tofind and mate with males of high quality,coping withthe restrictions of the subterranean environment.
基金Financial support was provided by the Spanish Ministerio de Ciencia,Innovación y Universidades project PGC2018-093592-B-I00(MCIU/AEI/FEDER,UE).
文摘Arid climates are characterized by a summer drought period to which animals seem adapted.However,in some years,the drought can extend for unusually longer periods.Examining the effects of these current extreme weather events on biodiversity can help to understand the effects of climate change,as models predict an increase in drought severity.Here,we examined the effects of“unusual”extended drought on soil invertebrate prey availability and on diet composition(based on fecal contents)and diet selection of a fossorial amphisbaenian,the checkerboard worm lizard Trogonophis wiegmanni.Weather data show interannual variations in summer drought duration.The abundance and diversity of soil invertebrates in spring were high,and similar to those found in a“normal”early autumn,after some rain had ended with the summer drought.In contrast,in years with“unusual”extended drought,abundance,and diversity of soil invertebrates in early autumn were very low.Also,there were seasonal changes in amphisbaenians’diet;in autumn with drought,prey diversity,and niche breadth decreased with respect to spring and autumns after some rain had fallen.Amphisbaenians did not eat prey at random in any season,but made some changes in prey selection that may result from drought-related restrictions in prey availability.Finally,in spite that amphisbaenians showed some feeding flexibility,their body condition was lower in autumn than in spring,and much lower in autumn with drought.If extended drought became the norm in the future,amphisbaenians might suffer important negative effects for their health state.
基金Financial support was provided by the Spanish Ministerio de Ciencia,Innovación y Universidades project PGC2018-093592-B-I00(MCIU/AEI/FEDER,UE).
文摘Melanin is the basis of coloration in many animals,and although it is often used in communication,thermoregulation,or camouflage,melanin has many other physiological functions.For example,in polluted habitats,melanin can have a detoxifying function.Melanic coloration would help to sequester in the skin the heavy metal contaminants from inside the body,which will be expelled to the exterior when the skin is sloughed.Moreover,animals should have evolved more melanic colorations in more polluted habitats(“industrial melanism”hypothesis).We examined whether the fossorial amphisbaenian reptile,Trogonophis wiegmanni,is able to eliminate heavy metals,derived from soil pollution by seagull depositions,through sloughing its skin.Our results suggest a covariation between levels of soil pollution by heavy metals and the concentration of heavy metals in the sloughed skins of amphisbaenians.This suggests that amphisbaenians may expel heavy metals from their bodies when they slough the skins.We also tested whether amphisbaenians inhabiting soils with higher levels of heavy metal pollution had darker(melanin-dependent)body colorations.However,contrary to predictions from the“industrial melanization”hypothesis,we found a negative relationship between soil pollution and proportions of melanic coloration.This contradictory result could,however,be explained because heavy metals have endocrine disruption effects that increase physiological stress,and higher stress levels could result in decreased melanogenesis.We suggest that although amphisbaenians might have some detoxifying mechanism linked to melanin in the skin,this process might be negatively affected by stress and result ineffective under conditions of high soil pollution.
