Ecological correlates of the threat of extinction in neotropical bird species

Predicting the threat of extinction aids efficient distribution of conservation resources. This paper utilises a comparative macroecological approach to investigate the threat of extinction in Neotropical birds. Data on ecological variables for 1708 species are analysed using stepwise regression to produce minimum adequate models, first using raw species values and then using independent contrasts (to control for phylogenetic effects). The models differ, suggesting phylogeny has significant effects. The raw species analysis reveals that number of zoogeographical regions occupied, elevational range and utilisation of specialised microhabitats were negatively associated with threat, while minimum elevation and body mass were positively associated, whereas the independent contrasts analysis only identifies zoogeographical regions as important. Confining the analysis to the 582 species restricted to a single zoogeographical region reveals elevational range and number of habitats occupied to be negatively correlated with threat whether the analysis is based on the raw data or on independent contrasts. Analysis of four contrasting zoogeographical regions highlights regional variation in the models. In two Andean regions the threat of extinction declines as the elevation range across which the species occurs increases. In the presence of substantial human populations on high Andean plateaus, a species with a greater elevational range may be more likely to persist at some (relatively) unsettled altitudes. In Central South America, the strongest predictor of threat is minimum elevation of occurrence: species with a lower minimum are less threatened. The minimum elevation result suggests that lowland species experiencing an ecological limit to their minimum elevation (min. elevation >0 m) may be more at risk than those not experiencing such a limit (min. elevation = 0 m). Finally, in southern Amazonia, where there is little altitudinal variation, the only weak predictors of threat are body size, larger species being more threatened, and number of habitats, species occupying more habitats being less threatened. These contrasting results emphasise the importance of undertaking extinction risk analyses at an appropriate geographical scale. Since the models explained only a low percentage of total variance in the data, the effects of human-mediated habitat disturbance across a wide range of habitats may be important.

Exploratory surgery of the female psyche

The thesis explores the visual narrative concerning a journey of empowerment for women. To enable the journey to advance the inquiry is directed into two areas. The first area is female gender, which is argued to be socially constructed and implicit in the marginalisation of women in western society. The second area is ‘feminine authority’, which is gained by developing an understanding and acceptance of the characteristics which have historically been considered as belonging to the feminine. Granting these characteristics agency would recognise their authority and assist in the elevation of the female to a position of equality in western society. Beginning from a feminist position, the research supported the belief that the female is marginalised in western society. It also confirmed the notion that empowerment and authority can be attained by women if they actively pursue the following; • Explore their own psychology beyond the existing socially constructed gender roles. • Develop an understanding of their feminine self by applying Jung's theories on individuation and archetypes. • Expose the underlying patriarchal influence in western epistemology and science by challenging existing deeply held cultural and scientific beliefs and by actively contributing as feminists to the areas of epistemology and science. Archetypal myths of the ‘feminine’ have developed from an androcentric position. They enforce and perpetuate gender imbalance which contributes to the disenfranchisement of women in western society, ‘Individuation’ is a process in which a person explores aspects of themselves to bring forth parts of their unconscious into their conscious mind in an attempt to gain a deeper understanding of themselves. As a consequence the consciousness develops closer links with archetypal memories which assists the exploration. The ‘true feminine’ is the feminine not restricted or defined by the dominant androcentric view. Knowledge of the feminine empowers women to address the marginalisation of the female in western society and assists in the process of gaining female authority. This enquiry also investigated the four stages of female psychological development with regard to patriarchal influences. Of particular importance is the second stage of psychological development where the female identifies with historically perceived inferior characteristics of the female. This is when she rejects her connections with the primacy of female power and her deep connections with nature which were inherited from archaic times. It is at this stage that she absorbs the myths associated with western patriarchal society which effectively disempower her. Western epistemology, with its emphasis on ‘objective’ investigation and empiricism contributes to the support for and promotion of ‘inferior’ female gender. This type of investigation is brought into question when areas of research into primates and human evolutionary theory is shown to develop from an androcentric view. Western knowledge has associations with power and justice and power is commonly associated with dominance. Regard for ‘truth’ and ‘absolute’ can be viewed as key elements in the support for knowledge and its associations with power. Knowledge has historically maintained suppression of individual experience which promotes a universalised account. This suppression of beliefs other than the dominant authority maintains the existing dominant social structure. Foucault's view of the genderised or inscribed body alerts us to areas where dominance, resistance and power play a part in maximising masculine power and control. Gender becomes an instrument of power within the existing patriarchal structure. Gender, knowledge and power are identified as areas obstructing female empowerment. Part 3 of this exegesis examines the imagery which embodies the visual narrative. Particularly, the harlequin image, its historical background and connections with ancient mythology including reference to Jungian psychology. The harlequin image is developed sequentially in the earlier black and white drawings on paper. These drawings contained a female figure which was often placed in juxtaposition with a Venus or goddess image, reference was also made to ‘eve’ and the ‘siren’. These elements provided the framework which enabled the harlequin image to emerge and evolve. The narrative developed with an understanding of the ‘feminine’ aspects of the psyche which resulted in the harlequin acquiring the elevated authority of a goddess. The Harlequin evolved from my need for symbolic representation of the female psyche. It represents contradiction and dualism. It is a composition of opposites, reflects masculine and feminine traits, the dark and light of the conscious and unconscious mind, it houses both comic and sinister elements, is a trickster and menace. The costume, colours and patterns are expressive elements conducive to fragmentation and layering within the composition of the paintings. Jung examined the harlequin in Picasso's paintings. He concluded that as Picasso drew on his inner experiences the harlequin became important as a symbol; it was a pictorial representation from the unconscious psyche. It travelled freely from the conscious to the unconscious and represented the masculine and feminine, chthonian and apollonian. The final painting in the series, a triptych, completes the narrative and stands alone as a salutatory work. It unites the series by combining existing compositional devices and technique while making reference to imagery from previous works, ‘The Three Graces Victorious’, expresses the authority of the feminine. It completes a victorious stage of a journey where the harlequin is empowered by archaic memories and knowledge of the psyche. The feminine is hailed, elevated and venerated. Other elements which assist in expressing the visual narrative are; colour, technique and influence. Colour is explored and its use as an emotive devise in expressionism. Paul Klee's writing on the use of colour and it's symbolic meaning and Julia Kristeva's investigation on colour from a psychoanalytic and semiotic view are also discussed. To indicate influences and connections within my oeuvre, reference is also made to the following: Jasper Johns' for his use of imagery in his ‘Four Seasons’ series with it's reference to a journey of maturation and Louise Bourgeois' work which deals with issues of gender, memories and past journeys. Although ‘The Three Graces Victorious’; the concluding painting for the investigation is celebratory and represents a finality to the thesis, it points to further areas that impede feminine development and need future examination. Reference is made to a continuation of the exploratory journey by plotting the Harlequin/Goddesses future directions. Although the Harlequin/Goddess is empowered with newly acquired authority, her future journey does not need to be bound by mathematics or limited by rationality. She does not require power to dominate or gender structures to subjugate, but requires limitless boundaries and contexts. The Harlequin/Goddess's future journey is not fixed.

Ecological and life-history factors influencing the evolution of maternal antibody allocation : a phylogenetic comparison

Maternally derived yolk antibodies provide neonates with immune protection in early life at negligible cost to mothers. However, developmental effects on the neonate's future immunity are potentially costly and thus could limit yolk antibody deposition. The benefits to neonatal immunity must be balanced against costs, which may depend on neonate vulnerability to pathogens, developmental trajectories and the immunological strategies best suited to a species' pace of life. We measured yolk antibodies and life-history features of 23 species of small Neotropical birds and assessed the evidence for each of several hypotheses for life history and ecological effects on the evolution of yolk antibody levels. Developmental period and yolk antibodies are negatively related, which possibly reflect the importance of humoral immune priming through antigen exposure, and selection to avoid autoimmunity, in species with a slower pace of life. There is also a strong relationship between body size and yolk antibody concentration, suggesting that larger species are architecturally equipped to produce and transfer higher concentrations of antibodies. These results suggest that developmental effects of maternally derived antibodies, such as imprinting effects on B-cell diversity or autoimmune effects, are important and deserve more consideration in future research.

Temporal expression of heat shock proteins 60 and 70 at lesion-prone sites during atherogenesis in ApoE-deficient mice

In the study, we investigate whether the expressions of heat shock protein (hsp)60 (a potential autoantigen) and the stress-inducible form of cytoprotector hsp70 are correlated with the development of atherosclerotic lesions in the aortic tree of apolipoprotein E–deficient (apoE^-/-) mice. The apoE^-/- mouse model is advantageous because the stress-inducible form of hsp70 is not constitutively expressed in mice, unlike primates; hence, tissues under stress can be clearly defined. Both mammalian hsps were detected newly expressed (before mononuclear cell infiltration) on aortic valves and endothelia at lesion-prone sites of 3-week-old apoE^-/- mice. In 8- and 20-week-old mice, they were strongly and heterogeneously expressed in early to advanced fibrofatty plaques, with levels correlating with lesion severity. Expression was markedly downregulated in advanced collagenous, acellular, calcified plaques of 40- and 69-week-old mice and was absent in control aortas of normocholesterolemic wild-type (apoE^+/+) mice. Western blot analysis of tissue homogenates confirmed the temporal expression of the hsps. Double immunostaining revealed that both hsps were expressed by lesional endothelial cells, macrophages, smooth muscle cells, and CD3⁺ T lymphocytes. This study provides evidence that hsp60 and hsp70 are temporally expressed on all major cell types in lesion-prone sites during atherogenesis, suggesting that few cells escape the toxic environment of the atherosclerotic plaque.

Declining woodland birds - Is our science making a difference?

Recent data from the Red List of the International Union for the Conservation of Nature show that 1240 of the world’s estimated 10 027 species of birds (12.4%) are listed as threatened (Hoffmann et al. 2010). Globally, many more are ‘declining’ in conservation status. In Europe, much attention has been given to the marked decline in the abundance and distributional extent of farmland birds associated with the intensification of agricultural production (Fuller et al. 1995; Donald et al. 2001). Recent analyses suggest woodland species alsomaynowbe experiencing significant declines (e.g. Hewson et al. 2007). In the Americas, the declining status of neotropical migrants has motivated considerable research over the last 30 years (e.g. Terborgh 1989; Robinson and Wilcove 1994). In the tropics, narrowly endemic land birds have been identified as those species most at risk of decline globally in coming decades owing to projected changes in land-use (Jetz et al. 2007). Particular taxonomic groups also are experiencing marked declines. Migratory shorebirds, for example, which depend on key stop-over sites for refuelling during intercontinental migration, are particularly vulnerable to the degradation and destruction of these sites (Barter 2002; Rogers et al. 2010). Such widespread change among the world’s avifauna has profound implications for global biodiversity, ecosystem function and the provision of ecosystem services (Sekercioglu 2006).

Noisy neighbours at the frog pond: effects of invasive cane toads on the calling behaviour of native Australian frogs

Invasive species can disrupt the communication systems that native biota use for reproductive interactions. In tropical Australia, invasive cane toads (Rhinella marina) breed in many of the same waterbodies that are used by native frogs, and males of both the invader and the native taxa rely on vocal signals to attract mates. We conducted playback experiments to test the hypothesis that calls of toads may influence the calling behaviour of frogs (Limnodynastes convexiusculus and Litoria rothii). Male L. convexiusculus adjusted their calling rate and the variance in inter-call interval in response to a variety of sounds, including the calls of cane toads as well as those of other native frog species, and other anthropogenic noise, whereas L. rothii did not. Within the stimulus periods of playbacks, male L. convexiusculus called more intensely during long silent gaps than during calling blocks. Thus, males of one frog species reduced their calling rate, possibly to minimise energy expenditure during periods of acoustic interference generated by cane toads. In spite of such modifications, the number of overlapping calls (within stimulus periods) did not differ significantly from that expected by chance. In natural conditions, the calls of cane toads are continuous rather than episodic, leaving fewer gaps of silence that male frogs could exploit. Future work could usefully quantify the magnitude of temporal (e.g. diel and seasonal) and spatial overlap between calling by toads and by frogs and the impact of call-structure shifts on the ability of male frogs to attract receptive females.

Effects of visual contact with zoo visitors on black-capped capuchin welfare

Previous research has suggested that the presence of zoo visitors may be stressful for various primate species, and visual contact with visitors may be the sensory stimuli that mediate visitor effects. We studied a group of black-capped capuchins, Cebus apella, in a controlled experiment, randomly imposing two treatments: customised one-way vision screens on the exhibit viewing windows to reduce visual contact with visitors; and unmodified viewing windows that allow full visual contact with visitors. We sampled capuchin behaviour including intra-group aggression and other social interactions, vigilance and abnormal behaviours. To provide a measure of physiological stress, we also analysed capuchin faecal samples for glucocorticoid metabolite (FGM) concentration. When the view of visitors was obscured, we found marked reductions in capuchin aggression (from 14.5 bouts to 4.6 bouts per weekend, P= 0.004) and FGM concentration (from 620 to 410. ng/g, P= 0.008) among all adults, as well as reductions in abnormal behaviour (P = 0.01) in two individuals. The capuchins also avoided the visitor viewing area (P = 0.003) in the unmodified viewing window treatment. These results suggest that reducing the capuchins' ability to view visitors improved their welfare. However we also found a reduction in the number of visitors when visual contact was reduced (from an average of 23 visitors per scan to 15, P = 0.008), suggesting that the visitor experience may have been compromised by the lack of interaction with the capuchins. These results highlight a possible dilemma for the zoo industry between enhancing animal welfare in primates and providing for visitor experience.