The normal depth usage of the juvenile lemon shark, <i>Negaprion brevirostris </i>was determined using data storage tags which logged pressure and temperature.  Sharks were found to predominantly occupy water depths between the surface and 1m.  A diel rhythm and a tidal rhythm were found for the pressure data.  Simultaneous acoustic tracking showed shallow water use despite the availability of deeper areas within the sharks’ home ranges.  All sharks mainly occupied a narrow range of temperatures (29°C - 31°C) at the high end of their range.  Temperature data showed mainly diel rhythms with slight tidal influence.  Pressures and temperatures used by the sharks seemed to be affected by size of home range, individual preference and predator avoidance.  The behaviour of the lesser spotted dogfish <i>Scyliorhinus canicula </i>was investigated during controlled small steps of pressure inside a hypobaric chamber.  Swimming occurred in response to decreasing pressure with increased swimming speed and duration suggesting enhanced sensitivity of the shark pressure sensor within  a narrow range between 39mbar above and down to 195mbar below barometric pressure.  Further studies using a novel tidal tank system showed that <i>Scyliorhinus </i>synchronised their activity with a 12.5 hour tidal cycle but not with a 9  hour cycle.  When different resting depths were made available, they were utilised by dogfish, suggesting an individual preference independent of environmental cues or the presence of the opposite sex.  Isolated vestibular systems were challenged over a range of pressures. Hair cell afferent activity showed responses to sinuosoidal cycles and step changes of pressure.  Temperature effects are complex but were small compared with pressure effects.  Knowledge of the pressure sensor and vertical range used by sharks is essential in the present development of marine protected areas in an attempt to ultimately aid the conservation of sharks.

No description available.

Joyful expressions of one-year-old infants were studied in naturalistic contexts in infants’ home environments. Chimpanzee infants (n = 7) and human infants from the Cameroon Nso community (n = 8) were studied in their own right and in comparison. Similar methodologies and the development of a single coding scheme allowed direct comparisons between the groups. The research aims to contribute to knowledge about 1) emotion socialisation; 2) the whole-body expression of emotions in infancy; 3) the evolutionary heritage of emotions; and 4) the functions of joyful emotions. Playful behaviours were analysed for play type, infant joy (facial, motor, and vocal1), play partners and their engagement, and matching of infant joy by play partners. The first study (Chapter 4) describes the play contexts of chimpanzee infants from two settings (Chester Zoo, UK, and Primate Research Institute (PRI), Japan), as there was little published quantitative data specific to one-year-old chimpanzees. Play contexts were similar across settings though the proportion of time spent in the different types of social play varied with more rough-and-tumble play at Chester Zoo (larger group, juveniles present) and more tickling by mothers at PRI. The second study (Chapter 5) describes the joyful expressions of chimpanzee infants. Facial and motor joy occurred at similar rates overall though the rate of facial joy was skewed towards social contact and tickling play to a greater degree than motor joy. Mothers elicited a particularly high rate of infant joy (often during tickling) but peers matched a greater proportion of infant joy (often during contact play). The third study (Chapter 6) describes the joyful. Vocal joy was analysed for human sample only expressions of human infants. Facial, motor, and vocal joy occurred at similar rates overall though rates of facial joy and vocal joy were skewed towards social communicative and rhythmic play to a greater degree than was motor joy. Play partners matched a greater proportion of infant joy during social communicative and rhythmic play and social object exchange than during other types of social play. The fourth study (Chapter 7) compares the joyful expressions of chimpanzee infants and human infants. The rate of facial joy was equivalent in both groups despite differences in the contexts of play, underlining the importance of joy to infant development in both species. Differences were evident in the rate of motor joy (higher in the human sample) and in matching of infant joy (marginally higher in the human sample, variation by play partners). The general discussion highlights key findings in relation to the socialisation of joy (e.g. the high rates of joy during play contexts which support social cohesion, the different roles of mothers and peers/older children in eliciting and responding to infant joy) and the whole body expression of joy (the distinctive patterns of facial, motor and vocal joy across social and solitary play contexts). Findings are discussed in relation to theories about the functions of joy.

Sexual dimorphisms in head morphology, integument and dentition of some elasmobranch species have been established. These dimorphisms are reportedly linked to reproductive behaviour, whereby male biting during copulation results in a dimorphism in head dimensions and dentition and, as a result, differences in skin thickness. The findings for Scyliorhinus canicula from the Solent support the findings of other authors, whereby adult males were found to possess longer, narrower mouths and a longer head than adult females. Juvenile male catsharks were found to possess a longer mouth than females. No head, mouth or jaw dimorphisms for hatchling catsharks were found. Adult male catsharks were found to possess unicuspid teeth, with large central cusps, in contrast to the pentacuspid form of female and immature catsharks. A sexual dimorphism was found in the tooth row numbers for hatchling and adult catsharks, with hatchling males possessing a greater number of tooth rows than hatchling females on the lower jaw and adult males possessing a greater number of tooth rows than adult females in the upper jaw. Seasonal comparisons were made to ascertain whether morphological changes occurred that could indicate a mating season for the Solent population of S. canicula. Adult head length, mouth length and mouth width were found to be significantly different. Adult males sampled in all seasons possessed a longer mouth than females sampled in all seasons, whilst the lower jaw length was significantly greater for adult males in all seasons compared to adult females. Juvenile female catsharks were found to possess a thicker epidermis than juvenile male catsharks in all seasons of the year, whilst adult females possessed a thicker epidermal layer than adult males, findings not previously reported in this species. Adult females were found to possess a thicker dermal layer in all seasons compared to adult male catsharks. Adult females also possessed wider and longer dermal denticles on the pectoral fins than adult males. Hatchling catsharks had a greater dermal denticle density on both fins indicating the possession of smaller dermal denticles than hatchling females. A sexual dimorphism was found in the Ampullae of Lorenzini with male catsharks possessing a greater number of alveoli than adult females, possibly both an ecological and reproductive adaptation. The seasonal and sexual dimorphisms found in this study do not directly indicate a specific mating season for this species in the Solent.

In my thesis I investigate the ecology of maternal influences: the unique ability of mothers to influence, via genetic and non-genetic means, the phenotypic expression of their offspring. My research is presented as a series of standalone chapters that are introduced and then summarised by a general introduction (Chapter 1) and a general discussion (Chapter 6) respectively. One of the main components of an organism’s energy budget is its baseline level of energy metabolism. Individual differences in this cost of self-maintenance (termed in this chapter, resting metabolic rate, RMR) are substantial, but the causes and consequences of this variation are obscure. In Chapter 2, I review the published literature and show that maternal influences (along with other factors) can contribute substantially to variation in offspring RMR. Also, the RMR - fitness relationship appears to be modulated by environmental conditions (e.g. food supply), suggesting that the fitness consequences of a given RMR may be context-dependent. Thus, I propose that broad-scale variation in RMR might persist in natural populations, due to both spatial and temporal variation in environmental conditions and the trans-generational influence of mothers. To further investigate maternal influences on offspring energy metabolism, I measured the standard metabolic rate (SMR, a measure equivalent to RMR but used in reference to ectothermic animals) of juvenile brown trout (Salmo trutta) in response to intra-clutch manipulations of egg cortisol and testosterone (Chapter 3). Although, neither hormone affected offspring SMR (egg testosterone treatment resulted in a likely pharmacological dose), juveniles from cortisol-treated eggs were smaller and subordinate to individuals from control eggs. This indicates that variation in the amount of cortisol deposited in eggs by females, either among clutches or within them, is likely to affect juvenile performance. In a separate experiment (Chapter 4), I investigated if within-clutch differences in the phenotypes of juvenile brown trout were systematically related to the position where each individual developed during oogenesis. For a given egg size, siblings from dominant mothers were initially larger (but had a lower mass-corrected SMR) if they developed in the rear of the egg mass. However, heterogeneity in the size of siblings from different positions in the egg mass diminished in lower ranking females. Juvenile social status also varied according to egg mass position, although the direction of this effect depended on their age. Maternal influences on offspring are not only determined by conditions experienced by females immediately prior to reproduction. In Chapter 5, I investigated whether the juvenile growth rate and adult reproductive traits of female wild Atlantic salmon are related to the performance of their offspring in the wild. Investment in egg size was linked to both the juvenile and adult phenotypes of mothers. Even when controlling for egg size, the influence of these ‘past’ and ‘present’ maternal traits extended to offspring performance. Offspring growth was positively related to maternal investment in reproduction and the juvenile growth rate of each mother. The survival and biomass of offspring were also linked to adult reproductive traits but these relationships differed for mothers that had grown at either fast or slow rates as juveniles. Overall my thesis demonstrates that maternal influences are a substantial source of variation in offspring size, behaviour and physiology, both among and within clutches. My research also underlines the importance of maternal influences for offspring ecology and therefore maternal fitness.

No description available.

Animals often respond differently to the same environmental cues. Where behavioural responses differ consistently between individuals over time or contexts, this is “personality”. In wild animals, personality is linked to variation in fitness and survival. Predictions on the behavioural mechanisms underlying this variation come from captive studies, on the often untested assumption that captive behaviour reveals how animals would behave in the wild. In chapter 2, using blue tits (Cyanistes caeruleus) I tested first whether behaviour in captivity predicted foraging behaviour in the wild. I measured the personality traits neophobia (latency to feed in novel scenarios) and exploratory tendency, first by relatively standard captive protocols and second, using an electronic monitoring system at feeding stations, by novel wild methods. As predicted, analogous traits correlated across contexts. Moreover, neophobia and exploratory tendency were uncorrelated within individuals in both contexts, in contrast to many other species. In captive studies, personality types also respond differently to changing environmental cues, or “environmental sensitivity”: neophobic and non-exploratory types adjust behaviour whilst neophilic and exploratory types maintain foraging routines. In chapter 3, I tested this second captive prediction in the wild, defining environmental sensitivity in the wild by changes in feeder use with varying air temperature or food supply. Neophobic and, contrary to expectation, exploratory blue tits were most environmentally sensitive. By contrast, neophilic and nonexploratory birds visited feeders at a fixed level independent of temperature and continued to visit feeders for a prolonged period even after they were emptied. Age and body size also influenced environmental sensitivity, suggesting learning and dominance interactions modify the expression of personality in the wild. From potential behavioural costs, in chapter 4 I turned to the physiological costs of personality. Variation in metabolic rate and stress metabolism may be proximate mechanisms for personality. Whilst these physiological traits are linked to oxidative stress directly, with pro-oxidants that damage body tissue a by-product of metabolism, few studies link personality to oxidative stress. I found that oxidative profile (pro-oxidants, antioxidants, oxidative stress and oxidative damage) and hence physiological costs differed notonly within traits but also related differently to neophobia and object exploration in captive-bred greenfinches (Carduelis chloris). Finally, variation in response to environmental cues may reflect differences in learning between individuals, as perhaps illustrated by age differences in environmental sensitivity (Chapter 3). In chapters 5 and 6, I investigated whether learning that a feeding site is temporally stable could cause changes in response to food appearance (“local cues”) when foraging. I predicted that birds would re-find food by spatial rather than local cues in these scenarios, as appearance can change hence local cues become unreliable over time. In chapter 5, I carried out an associative learning test to test this prediction in captive-bred greenfinches. Within a simple foraging scenario, the prediction was upheld: greenfinches favoured local cues in situations where the temporal stability of food was unknown, but switched to spatial cues when temporal stability was learnt through repeated encounters. In chapter 6 though, four of five wild bird species foraging at temporally stable bird feeders continued to respond to local cues, selecting feeders on the basis of colour. Most species were biased toward red feeders, and also responded to social cues when finding feeders: foraging strategies better suited to finding ephemeral food than re-finding temporally stable feeding sites. I suggest that wild birds use information on temporal stability from the broader environment (i.e. natural ephemeral food beyond temporally stable artificial feeders). This illustrates how animals may not necessarily forage in the wild as we would expect within specific contexts. Throughout this thesis therefore, my findings illustrate the importance of testing predictions generated from captive behaviour in the wild. Moreover, identifying variation in both the foraging strategies and physiological costs to individual variation in behaviour, this thesis provides new insight into the adaptive significance of animal personality.

Kin recognition allows individuals to assess their relatedness to conspecifics, thus they may then show kin discrimination and make informed choices as to with whom to associate and/or breed. Cooperatively breeding species, such as the cichlid Neolamprologus pulcher, are an excellent model system for investigating kin recognition, as they live in complex social groups, containing both kin and non-kin group members. Cooperation involves individuals helping to rear the offspring of the dominant pair. Helping is costly, but helpers may gain direct fitness benefits through living in a group, and if they aid relatives, they can also gain indirect fitness benefits through kin selection. Furthermore, by being able to recognise kin, individuals can also avoid inbreeding and the potentially deleterious consequences of it. Thus, N. pulcher are predicted to have good kin recognition abilities. In this thesis, I investigate kin recognition and its consequences for helping and mate choice in a captive population of N. pulcher. In chapter 2, I investigated the kin recognition capabilities of juvenile N. pulcher whilst controlling for familiarity. I found that N. pulcher preferred to associate with unfamiliar kin over unfamiliar non-kin. Kin recognition was via some form of phenotype matching, with chemical cues being more important than visual cues. Additionally, I found no discrimination between familiar and unfamiliar kin; thus, relatedness rather than familiarity was important in the association preferences of juvenile N. pulcher. Chapter 3 explored whether relatedness to the breeding pair, or differences in individual behavioural types affected the amount or type of helping shown by N. pulcher. Controlling for group size and helper relatedness, I found that the relatedness of the helpers to the breeders had no influence on the amount or type of help carried out. Thus, kin selected benefits alone cannot explain variation in helping behaviour in N. pulcher. The amount of territory maintenance carried out correlated with the amount of territory defence, thus, some individuals were consistently helpful. Individuals varied consistently in their aggressiveness, risk-responsiveness and activity levels, but these traits did not correlate with one another. More aggressive, risk-prone or more active helpers carried out more territory defence than submissive, risk-averse or inactive helpers. In contrast, the amount of territory maintenance carried out by helpers, was not correlated with the behavioural types. Thus, differences in behavioural types explained more variation in helping behaviour in N. pulcher than relatedness. Since motivation to associate with kin might vary with age and individual state, in chapter 4, I investigated whether N. pulcher avoided kin when sexually mature, and examined the fitness consequences of inbreeding. In standard two-way choice tests, I found that whilst male N. pulcher showed no preferences for associating with sisters over female non-kin, female N. pulcher preferred to associate with brothers over male non-kin. However, when given the opportunity to breed, latency to breed and hatching success did not differ between brother-sister pairs and unrelated pairs. Thus, in N. pulcher inbreeding is not actively avoided and does not appear to be detrimental to fitness. I suggest that sex-biased dispersal and regular breeder replacement on territories may minimise the occurrences of inbreeding in the wild and that inbreeding may be opportunistic, rather than a strategic decision. The final theme of my thesis investigated the effect of phenotypic traits on mate choice. In N. pulcher (chapter 4) I found that the size of an individual’s facial stripe, which varies between individuals, played no role in mate association preferences. I then investigated male mate choice for female body size in the non-cooperatively breeding green swordtail, Xiphophorus hellerii. In chapter 5, I found that males showed preferences for large over small females when presented only with visual cues, but not with only chemical cues. However, as the size differential between the large and small female increased, males showed preferences for the larger female based on chemical cues. So, male X. hellerii prefer larger females, which are predicted to be more fecund and hence, bring them greater fitness returns. In conclusion, my study has shown that N. pulcher can recognise kin, but the ability to do this does not compel individuals to show kin directed cooperation, or inbreeding avoidance. Instead, factors such as an individual’s behavioural type have more influence on decisions to help, and inbreeding does not appear to be detrimental to fitness. Overall, this project shows that under the conditions we tested, kin selection alone does not drive the social interactions in N. pulcher groups. Further, it highlights the need to consider multiple factors affecting an individual’s fitness, in order to fully understand why different species show a propensity to recognise and discriminate between kin and non-kin.

Male crustaceans must find and identify receptive females to mate successfully. Mate recognition depends mainly on sex pheromones, which are detected by antennae and antennules. Distance (soluble)pheromone mediates mating behaviour of some decapod crustaceans. Contact pheromone (an insoluble coating on the body surface) has been proposed but not confirmed to be used by male decapod crustaceans to detect females. Here we report for the first time the involvement of both distance and contact pheromones in the mating processes of Lysmata shrimp (a group of protandric simultaneous hermaphrodites), and we have partially identified the soluble and contact pheromones. Additionally, evolution of the sex pheromone system of Lysmata shrimp, and role of the sex pheromones in reproductive isolation of Lysmata shrimp were investigated.

The morphology and distribution of cuticular setae on the uropods and walking legs of the Norway lobster Nephrops norvegicus (L.) has been studied using both light microscopy and Scanning Electron Microscopy. Three types of setae are present on the uropods, plumose setae, simple setae and guard hairs. Hair peg and hair fan organs were also seen.The propodus and dactyl of the 2nd and 3rd legs of Nephrops are similar in both their structure and in the form and distribution of their cuticular setae. Three main areas of setal distribution are found: squamous setae are distributed 1) in bunches on the flat surfaces of the propodus and dactyl and 2) along the lateral edges of the propodus and dactyl and 3) hedgehog hairs line the inner edges of the propodus and dactyl.Most of the setae on the 4th and 5th legs are found around the propodus-dactyl (P-D) joint. Three rows of simple setae are found on the dactyl, and both serrate setae with simple scales and squamous setae are found overlapping the P-D joint. Also found near the joint are CAP organs and hedgehog hairs.All of the setae on the uropods show responses to tactile and vibratory stimulation as do the hedgehog hairs, the serrate setae, the simple setae and the squamous setae on the legs.The responses of afferents from the uropods and walking legs and of the abdominal interneurones have been tested in response to water borne vibrations of different frequences produced both as surface waves and in an acoustic tube. The uropod afferents show range fractionation and have therefore been divided into three nested categories based on the upper limit of their frequency response. Low frequency units respond from 2-20Hz, intermediate units from 2-50Hz and high frequency units from 2-100Hz. The leg afferents also show range fractionation and have also been divided into three nested categories: low frequency units respond from 20-60Hz, intermediate units from 20-200Hz and high frequency units from 20-450Hz. Preliminary studies have indicated that the leg afferents show directional sensitivity. The abdominal interneurones have been categorised as either intermediate or high frequency; intermediate interneurones respond from 2-100Hz and high frequency interneurones from 2-200Hz. The receptive fields of mechanosensory interneurones have also been determined.The postural responses of Nephrops to water borne vibrations have been studied using video analysis. An abdominal extension response is reliably elicited which varies with the frequency of stimulation in a distinct way. From 20-80Hz the animals respond immediately, and abdominal extension is accompanied by rapid leg movements, swimmeret beating and very occasionally tail flipping. From 100-180Hz the response occurs with a delay, the duration of which seems unrelated to frequency within this range. No responses were seen above 180Hz.The nervous control of the abdominal extension response has been studied by recording from abdominal motor roots (superficial root three and root two) which supply the two muscles involved (the superficial flexor and extensordmuscles). It has been shown that abdominal extension is produced by both central and peripheral inhibition of flexor muscle activity in combination with excitation of the extensor muscle. The neuronal basis of the delay seen in the behavioural experiments has been investigated, and a number different patterns of nervous activity have been found which might produce this delay.Behavioural studies have been conducted in the field to investigate the responses of freely moving animals to sound in their natural environment. Investigations have been conducted of changes in the emergence rhythm and changes in the transient behaviour of the animals. Tests to investigate changes in the burrow emergence rhythm with the underwater loudspeakers at 10m from the animal failed to produce any response. However small changes occur in the transient behaviour of Nephrops when they are very close to the loundspeaker even though the sound pressure levels are similar to those used at 10m. These tests have been repeated in laboratory tanks where clear locomotory responses, predominantly backwards walking, are seen in response to stimuli from 20-80Hz in both blind and sighted animals.Tests have been conducted in a free acoustic field to determine the behavioural response threshold of Nephrops to sound using the postural response as a monitor. The animals showed no responses with the loudspeaker at 1m but showed clear responses with the speaker at 0.09m even when the sound pressure levels were similar, yielding a threshold in terms of particle displacement of the water of 0.874m which is independent of frequency. This indicates that the Nephrops is sensitive to the particle motion component of sound rather than the pressure component.