Ornamental traits in male birds have been the subject of much research effort, and sexual selection is recognized as the leading explanation for their evolution. The expression of ornamental traits in females has received little study until recent decades. Female colouration has been considered a non-adaptive, correlated response to selection on males. However, models predict that male mate choice, female competition, and the evolution of honest signals could help explain female ornamentation, especially where male investment in offspring and variation in female quality are high. I investigated this in the American robin (Turdus migratorius), a socially monogamous species with bi-parental care and variable female ornamentation. Female robins display conspicuous red breast plumage, bright yellow bills, and achromatic ornamentation. Female ornamentation is similar to males, but is subdued to varying degrees across individuals. Female colouration could function as a useful criterion in mate selection by males if it is correlated with aspects of female quality important to producing viable offspring. I assessed whether female ornamentation in robins might act as an honest signal by relating variation in female colour to measures of individual quality and reproductive investment. To assess ornamentation, I took colour measurements of the bill, crown and breast of male and female robins in the field using reflectance spectrometry. Female bill, breast and crown traits reliably predicted age, crown and bill colour traits were related to better body condition, and bill colour decreased seasonally as well as with ectoparasite load. I found evidence of assortative mating based on crown UV reflectance and bill colour. To assess reproductive investment, I measured egg size, yolk proportion, and deposition of yolk testosterone and carotenoids. Females with brighter (lighter) carotenoid-based bill colour laid larger eggs, and females with yellower bills laid eggs with higher yolk proportions and more total yolk carotenoids. Yolk testosterone level was associated with redder female breasts. These results support the hypothesis that female colour may be a reliable indicator of individual quality and capacity for reproductive investment. / Thesis (Master, Biology) -- Queen's University, 2014-01-30 15:09:57.797

Investigating maternal investment (Ml) and mother-offspring relationships during the period of infant dependency is critically important to furthering the understanding of female reproductive strategies in primates. Infant primates are completely dependent upon their mothers. The way in which a mother allocates her resources therefore is crucial for infant survival, but is balanced Against her need to invest in subsequent offspring. One approach to examining how mothers might invest in their offspring stems from the Trivers & Willard hypothesis (TWH, 1973), which predicts that mothers in good condition should bias their investment towards sons and whereas mothers in poorer condition should bias investment toward daughters. Long-term demographic records on birth sex ratio and inter-birth interval suggest that female mountain gorillas (Gorilla beringei beringei) do not bias investment prenatally, but they may adjust postnatal Ml according to the TWH. This study investigated Ml and mother-offspring relationships in wild mountain gorillas, using behavioural correlates of Ml, including suckling, weaned age, physical contact, "transport, and grooming to redress the lack of understanding about Ml in this species. The appropriateness of TWH was investigated, integrating different indicators of maternal condition. Important determinants of Ml and mother-offspring relationships were considered, such as offspring age, parity, presence of siblings and maternal relatives, group size and lastly, personality, which has been largely neglected in nonhuman primates. The extent, to which the offspring influenced Ml patterns, was examined using the parent-offspring conflict theory (Trivers, 1972) as a theoretical framework. During 2006-2007, 38 mother-offspring dyads were observed in the Virunga massif, resulting in 1210 hours of direct behavioural observation. Additional field data from the previous four decades were integrated into the dataset for the analysis of suckling and weaned age. Gorilla personality was assessed through the Hominoid Personality Questionnaire. Findings relating to suckling frequency, weaned age, and maternal feeding activities were consistent with the TWH: sons suckled more often than daughters when they had mothers in good condition, whereas the reverse sex-pattern occurred in offspring with mothers in poorer condition. In addition, daughters were weaned at an earlier age than sons when mothers were in better condition, although this sex-difference reduced in older mothers that were categorised as being in good condition. Maternal feeding time and feeding efficiency revealed that mothers in poorer condition spent more time ingesting food when they had daughters, whereas mothers in better .condition spent more time ingesting food when they had sons. Furthermore, group size affected lactation duration with offspring in small groups being weaned earlier than offspring in large groups. Behavioural conflicts over Ml showed that the mother and offspring influenced Ml patterns during the period of dependency. Finally, six personality dimensions were identified, of which five revealed effects maternal behaviour, such as maternal retrieval, responsiveness and rejection, although their relative importance varied between those behaviours. In general, mother and offspring personality effects were complex due to their interactions with the developmental stage of offspring. In conclusion, my thesis research has made several novel contributions to furthering the understanding of female reproductive strategies in the highly endangered mountain gorilla. I presented the first evidence using behavioural data that females bias their postnatal investment towards the sex with the greatest fitness return as predicted by the TWH. My findings are discussed in the light of alternative Ml strategies, such as the local resource competition and enhancement model. My research has highlighted the importance of integrating anthropometric and physiological measures and demographic long-term data into future Ml studies to assess direct costs and benefits of Ml. The examination of mother-offspring behavioural conflicts showed that offspring have a strong impact on the level of Ml they receive. I have also examined the personality of a wild mountain gorilla population for the first time. My findings demonstrate that personality-parenting links are evident in several respects and I have demonstrated the great potential of personality as a determinant of maternal behaviour and mother-offspring relationships.

Most theoretical models predict an optimal offspring size that maximises parental fitness. Variation in the quality of the offspring environment can result in multiple offspring size optima and therefore variation of offspring provisioning can evolve. Variation in offspring provisioning is common and found across a variety of taxa. It can be defined as between populations, explained by optimality models, or between and within individuals, neither so easily explained by optimality models. My research focused on the evolution of variable offspring provisioning by testing theoretical models relating to variation in offspring provisioning between and within individuals. Using comparative methods, I found a positive relationship between intraclutch variation in offspring provisioning and variation in the quality of the offspring environment in a suite of pond breeding frogs. This positive relationship provided evidence that patterns of variable offspring provisioning are related to the offspring environment. This study also identified a species (Crinia georgiana) with high variation in offspring provisioning on which to focus further investigations. High variation in offspring provisioning occured between and within individuals of this species independent of female phenotype and a trade-off in offspring size and number existed. In laboratory studies, increased yolk per offspring led to increased fitness per offspring. Parental fitness calculations revealed that in high quality conditions production of small more numerous offspring resulted in higher parental fitness, but in lower quality conditions the production of large offspring resulted in the highest parental fitness. This was confirmed in field experiments under natural conditions using molecular markers to trace offspring to clutches of known provisioning, allowing me to measure exact parental fitness. The strategy of high variation in offspring size within clutches can be of benefit when the future of the offspring environment is not known to the parents: as a form of bet-hedging. Further study of the offspring environment revealed that conditions such as density dependent fitness loss, spatial variation in habitat quality, and non-random offspring dispersal, can combine to create the conditions predicted by theoretical models to maintain a strategy of variable offspring provisioning in the population. My research provides a comprehensive empirical test of the theory of variable offspring provisioning

Colony dynamics, maternal investment, and indicators of health were investigated for the New Zealand fur seal (Arctocephalus forsteri) over four austral summers, 2001- 2005. Effort was focused at the Ohau Point seal colony, north of Kaikoura. Two colonies at Banks Peninsula were included for comparisons of colony growth and pup condition. A range of other colonies were also included for making comparisons about colony dynamics and health indices. Colony dynamics were investigated through mark-recapture estimates of pup production and daily census of all individuals at the Ohau Point colony. Maternal attendance patterns were observed through behavioural observations of known females (n = 120), the use of VHF radio transmitters (n = 33), and female mass and body condition estimates (n = 51). Maternal investment was also investigated through longitudinal sampling of pup mass and growth rates. Parameters used to indicate colony health were: body condition, growth, presence of parasites, and the levels and common causes of mortality. The influence of parasites on pup growth was tested using treatment of selected pups with Ivermectin anti-helmentic medication, and mortality in the region was investigated through reports of dead individuals, and post mortems of those found fresh. The Ohau Point colony is in an exponential state of growth, and pup mass and condition was higher and responded to changes in environmental variables differently than at the Banks Peninsula colonies. Lactation lengths were consistently longer at Ohau Point than is typically reported for the species (323-355 days vs. 285 days). Maternal investment strategies were indicative of a close, reliable food source, and showed flexibility between years through extension of foraging trip durations and the increased use of overnight foraging trips. Individual strategies did not significantly influence pup growth. However, increased maternal condition and the ability to respond to inter-annual changes in resource availability resulted in accelerated pup growth even during an El Niño event. The incidence of pups with intestinal parasites was low at Ohau Point, and the average mass of treated and non-treated pups did not differ. Pup mortality in the region was low (3% to 50 days old), however, mortality of older pups was greatly influenced by the proximity of humans, with 2/3 of pup mortality observed between the age of 50 days and weaning being caused by car collisions. The results suggest that population dynamics and maternal investment in the region are greatly influenced by local variables, notably the presence of an accessible food source within close proximity to the colony. Various indicators of health reflect a growing colony in good condition, and the presence of a reliable food source may influence the maximum density and carrying capacity the colony is able to sustain. However, some concerns are raised about the influence of human interactions in the region, and how this may affect mortality and colony dynamics in the future. Extra fencing along the Ohau Point colony is recommended to provide added protection from the road. Continued monitoring of mortality and health indices in the region is also recommended for comparison with other colonies as Ohau Point reaches carrying capacity and density-dependent pressures increase.

The important part of life history of species is number and size of offspring, which is limited by size of maternal investment. Family of boas (Boidae) comprises species with various maternal investments. The species of study was Cuban boa (Chilabothrus angulifer) having small litter size, but producing one of the biggest neonates from family Boidae. The aim of the thesis was to analyze relationships between life-history parameters and try to find possible evolutionary causes of this huge maternal investment. Results show, that the female's decision to reproduce is under "Capital breeder" strategy, when size of the female positively influence litter size and offspring size. Surprising result is that smaller (younger) females are producing more sons than daughters in accordance with "Local resource competition" hypothesis. Fitness of the young should increase with birth size. That was confirmed only in interspecific survival rate being very high in Cuban boa. Keywords: snakes, Cuban boa, maternal investment, life history, SSD, sex ratio

<p>Understanding the diversity of life is one of the main aims of evolutionary biology, and requires knowledge of the occurrence and causes of adaptive genetic differentiation among geographically distinct populations. Environmental stress caused by acidity may cause strong directional selection in natural populations, but is little explored from an evolutionary perspective. In this thesis, a series of laboratory experiments and field data was used to study evolutionary and ecological responses of amphibians to environmental acidity. </p><p>Local adaptation to acid stress was studied in the moor frog (<i>Rana arvalis)</i>.The results show that acid origin populations have higher acid stress tolerance during the embryonic stages than neutral origin populations, and that acid and neutral origin populations have diverged in embryonic and larval life-histories. The mechanisms underlying adaptive differentiation are partially mediated by maternal effects related to extra-embryonic membranes and egg size. Acid origin females invest in larger eggs and have a stronger egg size-fecundity trade-off than females from neutral areas, likely reflecting adaptive differentiation in maternal investment patterns. </p><p>Potential carry-over effects of low pH, and the effects of UV-b/pH interaction were investigated in the common frog (<i>R. temporaria</i>). The results suggest that amphibian larvae are able to compensate for the negative effects of acidity experienced early in life, if conditions later turn beneficial. <i>R. temporaria</i> populations differed in their sensitivity to synergistic effects of low pH/UV-B, indicating variation in population responses to environmental stress.</p><p>In conclusion, these results suggest rapid evolution in response to human induced environmental change, much of which may be mediated via adaptive maternal effects. Acidification may be a powerful selective force shaping life-history evolution.</p>

Understanding the diversity of life is one of the main aims of evolutionary biology, and requires knowledge of the occurrence and causes of adaptive genetic differentiation among geographically distinct populations. Environmental stress caused by acidity may cause strong directional selection in natural populations, but is little explored from an evolutionary perspective. In this thesis, a series of laboratory experiments and field data was used to study evolutionary and ecological responses of amphibians to environmental acidity. Local adaptation to acid stress was studied in the moor frog (Rana arvalis).The results show that acid origin populations have higher acid stress tolerance during the embryonic stages than neutral origin populations, and that acid and neutral origin populations have diverged in embryonic and larval life-histories. The mechanisms underlying adaptive differentiation are partially mediated by maternal effects related to extra-embryonic membranes and egg size. Acid origin females invest in larger eggs and have a stronger egg size-fecundity trade-off than females from neutral areas, likely reflecting adaptive differentiation in maternal investment patterns. Potential carry-over effects of low pH, and the effects of UV-b/pH interaction were investigated in the common frog (R. temporaria). The results suggest that amphibian larvae are able to compensate for the negative effects of acidity experienced early in life, if conditions later turn beneficial. R. temporaria populations differed in their sensitivity to synergistic effects of low pH/UV-B, indicating variation in population responses to environmental stress. In conclusion, these results suggest rapid evolution in response to human induced environmental change, much of which may be mediated via adaptive maternal effects. Acidification may be a powerful selective force shaping life-history evolution.

Colony dynamics, maternal investment, and indicators of health were investigated for the New Zealand fur seal (Arctocephalus forsteri) over four austral summers, 2001- 2005. Effort was focused at the Ohau Point seal colony, north of Kaikoura. Two colonies at Banks Peninsula were included for comparisons of colony growth and pup condition. A range of other colonies were also included for making comparisons about colony dynamics and health indices. Colony dynamics were investigated through mark-recapture estimates of pup production and daily census of all individuals at the Ohau Point colony. Maternal attendance patterns were observed through behavioural observations of known females (n = 120), the use of VHF radio transmitters (n = 33), and female mass and body condition estimates (n = 51). Maternal investment was also investigated through longitudinal sampling of pup mass and growth rates. Parameters used to indicate colony health were: body condition, growth, presence of parasites, and the levels and common causes of mortality. The influence of parasites on pup growth was tested using treatment of selected pups with Ivermectin anti-helmentic medication, and mortality in the region was investigated through reports of dead individuals, and post mortems of those found fresh. The Ohau Point colony is in an exponential state of growth, and pup mass and condition was higher and responded to changes in environmental variables differently than at the Banks Peninsula colonies. Lactation lengths were consistently longer at Ohau Point than is typically reported for the species (323-355 days vs. 285 days). Maternal investment strategies were indicative of a close, reliable food source, and showed flexibility between years through extension of foraging trip durations and the increased use of overnight foraging trips. Individual strategies did not significantly influence pup growth. However, increased maternal condition and the ability to respond to inter-annual changes in resource availability resulted in accelerated pup growth even during an El Niño event. The incidence of pups with intestinal parasites was low at Ohau Point, and the average mass of treated and non-treated pups did not differ. Pup mortality in the region was low (3% to 50 days old), however, mortality of older pups was greatly influenced by the proximity of humans, with 2/3 of pup mortality observed between the age of 50 days and weaning being caused by car collisions. The results suggest that population dynamics and maternal investment in the region are greatly influenced by local variables, notably the presence of an accessible food source within close proximity to the colony. Various indicators of health reflect a growing colony in good condition, and the presence of a reliable food source may influence the maximum density and carrying capacity the colony is able to sustain. However, some concerns are raised about the influence of human interactions in the region, and how this may affect mortality and colony dynamics in the future. Extra fencing along the Ohau Point colony is recommended to provide added protection from the road. Continued monitoring of mortality and health indices in the region is also recommended for comparison with other colonies as Ohau Point reaches carrying capacity and density-dependent pressures increase.

No description available.

Chez les oiseaux chanteurs, le chant des mâles véhicule des informations sur l’émetteur et sert pour la défense du territoire ainsi que pour l’attraction et la stimulation des femelles en vue de la reproduction. Le bruit urbain masque une partie de ces chants qui servent aux femelles à évaluer la qualité des mâles en période de reproduction. Dans un premier temps, ce doctorat s’intéresse aux effets du bruit urbain sur l’évaluation de la qualité des mâles et les conséquences reproductives lors du choix de partenaire et de l’investissement maternel dans les œufs chez le canari domestique. Les résultats indiquent que le bruit urbain diminue la réceptivité sexuelle des femelles ainsi que leur investissement dans les œufs par un effet de masquage des chants qui perdent ainsi leur attractivité vis-à-vis des femelles. Ces résultats appuient l’idée que le bruit urbain perturbe la communication vocale et peut en partie induire une réduction des densités de populations d’oiseaux dans les zones bruyantes.La communication suppose le transfert d’information. Chez les oiseaux chanteurs, le chant reflète la qualité des mâles laquelle peut être liée à l’expérience de l’individu et donc dépendre de l’âge. Dans une seconde partie, ce doctorat s’intéresse aussi au rôle de l’âge dans la production des chants chez le rougequeue noir en situation de compétition intrasexuelle. Les résultats montrent que les mâles de rougegqueue discriminent l’âge de leurs compétiteurs sur la base de signaux acoustiques. Cependant, les mesures sur les chants n’ont pas pu mettre en évidence des marqueurs acoustiques variant avec l’âge. Ces résultats suggèrent la nécessité de prendre en compte les effets de l’âge dans la communication animale et les paramètres utilisés dans l’identification de l’âge. / In songbirds, male song conveys information about the emitter and has two main functions: the territorial defense on one side and the attraction and reproductive stimulation of the females on the other side. The urban noise partly masks male songs used by females to assess the quality of their potential breeding partner. In the first part of my thesis I investigated in the laboratory the impact of the urban noise on the females’ assessment of the male quality in terms of mate choice and maternal investment in eggs using the domestic canary as a model. The urban noise reduced the female sexual receptivity and their maternal investment in eggs when listening to highly attractive low-frequency male songs through a masking effect. My results support the idea that urban noise negatively impacts animal communication and may be one of the causes of the observed reduction in bird population densities living in noisy areas.Communication involves the transfer of information. In songbirds, songs reflect male quality which could be related to male experience and therefore to age. In the second part of my thesis I carried out a field study investigating the role of the age in song production during intrasexual competition using a migratory urban population of a highly territorial songbird, the black redstart. Males were able to discriminate the age of their rivals (one-year old versus older) on the basis of their songs. However, a detailed song analysis revealed no acoustic cues varying between one-year old versus older males. Our results confirm the importance of considering age effects in animal communication and the requirement to identify the cues used for these differential responses in relation to age classes.