Dr. Renée Marchin Prokopavicius
Title: Plant responses to heat and drought: which species can survive future climate conditions?
Abstract: As climate change progresses, urban plantings in many regions of the world are increasingly exposed to hot and dry climate extremes, posing new challenges for the health of urban vegetation. Extreme drought and heatwaves during the 2019-2020 austral summer caused the death of groundcover plants and widespread canopy dieback of street trees in Sydney, Australia. These warmer, longer, and more frequent droughts have been termed ‘global-change-type droughts’ and will require adjustment of current planting practices to favour selection of heat- and drought-tolerant plant species. Using standardised glasshouse experiments, 113 plant species – both native and exotic to Australia – were screened by exposing both well-watered and droughted plants to a six-day heatwave with maximum air temperature of 41°C. The aims were to (1) identify plant species or plant functional types that can tolerate heat and/or drought stress and (2) examine how trees respond physiologically to the combination of heatwaves and drought. In this talk, I will share results describing the ecophysiological responses of plants to heat and drought stress. The overall experimental approach shows promise for screening large urban floras and informing species selection of urban plantings, thus achieving green cities with greater resilience under future climate conditions.
Title: Bright lights, restless nights: effects of streetlights on sleep in urban birds
Abstract: Use of artificial light at night is a global and increasing issue. To reduce harmful effects on our sleep, most smartphones and computers now have software that reduces blue light in the evening. Could a similar approach also benefit wildlife? Here, I discuss the importance of considering sleep in ecology, the challenges of studying sleep, and results from two projects investigating the effects of streetlights on birds.
Professor Bob Wong
Title: Gobies in the desert: behaviour, genes and persistence in a challenging world
Abstract: The vast, arid interior of Central Australia is home to a unique freshwater fish fauna, among the most iconic of which, are desert-dwelling gobies in the genus Chlamydogobius. Adapted to a life of environmental extremes, desert gobies have proven to be an excellent model for understanding the role of environmental variation and arid connectivity in shaping the ecology, evolution and persistence of freshwater fishes in the desert. In this talk, I will discuss the origin of the Chlamydogobius group and the environmental drivers that have led to the diversification of these small, benthic fishes. I will also examine the role of behaviour and behavioural variation in contributing towards population and community stability, and how behavioural responses can help fish to exploit diverse habitats. Overall, the research contributes to our understanding of arid zone biodiversity, evolution, and the importance of behavioural traits for surviving under complex ecological conditions. In a contemporary setting, the findings also inform perspectives on the persistence and management of threatened desert fishes that are increasingly and urgently threatened by anthropogenic change.
Dr Serena Ding
Title: Collective behaviour in the roundworm C. elegans
Abstract: In complex biological systems, simple individual-level behaviours can give rise to emergent group-level phenomena. We investigate collective foraging in the roundworm C. elegans, using quantitative phenotyping and agent-based modelling to identify three behavioural rules underlying both aggregation and swarming: cluster-edge reversals, a density-dependent switch between crawling speeds, and taxis towards neighbouring worms. We further develop an on-lattice model to show that collective foraging may be beneficial for C. elegans in patchy food environments.
Professor Tim Landgraf
Title: Drones, bees and robofish - adventures in biorobotics
Abstract: The Biorobotics Lab works at the interface of biology and computer science to study the collective intelligence of model organisms (bees and fish). We have built a honeybee robot to study the bee dance communication system and fish robots for the analysis of collective behavior in guppies. We have strapped honey bees to drones and implanted electrodes in their brains to directly observe neural signals during visual navigation in the field. We use computer vision to track all bees in observation colonies and analyze the underlying social network dynamics. Every principle we discover in natural systems might have an application in technical systems, such as in swarms of autonomous cars, and this talk will provide an overview of the work we do as part of the Dahlem Center of Machine Learning and Robotics at the Institute of Computer Science.
Dr Emilie Ens and the Cross-cultural Ecology Lab
Title: Working to better understand and manage Australia’s biocultural assets through collaborative cross-cultural ecology.
Abstract: “Our ancestors were rangers, we have been rangers for over 40,000 years and are rangers today. It is our responsibility to look after those things… we are not doing this for ourselves, we are doing this for our country, for our people and for the sake of our culture; keeping our culture alive and strong” Cherry Wulumirr Daniels OAM https://www.youtube.com/watch?v=DCoPLvWO0QM.
Despite over 60,000 years of intergenerational knowledge gathering and environmental management and manipulation by Australia’s First People’s, it is surprising that Indigenous knowledge has only recently been recognised as valuable in land and sea management pursuits by non-Indigenous Australians. This recognition has been driven by mandates from international social and environmental justice fora, including Indigenous Rights (eg the UN DRIP 1992), Indigenous poverty (eg the Sustainable Development Goals) and inclusive environmental management strategies (eg the Convention on Biological Diversity and IPBES). In Australia, over the last decade or so we have seen rapid growth in Indigenous Ranger programs (eg Working on Country, 2007) and the Indigenous Protected Area program (1997), which now makes up about a third of Australia’s National Reserve System. Legislation such as state and territory Land Rights Agreements as well as the national Native Title Act 1993 have driven re-recognition of Indigenous land ownership and control with up to 75% of Australia’s land surface under some form of land claim. The Australian Environmental Protection and Biodiversity Conservation Act 1999 also acknowledges Indigenous rights and interests in Australia’s conservation agenda.
This international, national, state/territory and local movement now demands that ecologists and land managers collaborate with Indigenous land owners. However, we need to move beyond participation to include Indigenous Knowledge systems and methods and Country in environmental research and management. Over the last 12 years Emilie Ens has been learning how to do this with her Indigenous colleagues mainly from Arnhem Land, but also northern NSW and Cape York. In this talk Emilie and some of her postgrad students and Indigenous colleagues will share with you some their projects including how they were developed, what they found and the multiple benefits that have flowed from them to enhance Australia’s unique and linked bio-cultural diversity and assets.
Professor Alex Harmon-Threatt
Title: Saving native bees: Why we’re failing and what can we do better?
Professor David Kimbro and Professor Randall Hughes
Title: Studying predation risk and its nonconsumptive and trait-mediated indirect effects: are we making progress towards predicting field patterns? - David
Title: Studying predation risk and its nonconsumptive and trait-mediated indirect effects: are we making progress towards predicting field patterns? - Randall
Abstract: Over the last thirty years, a significant amount of theoretical and empirical research has successfully evaluated how predators can cause changes in prey traits (“fear” effects) that have substantial impacts on the prey, other species, and even ecosystem properties. A surprisingly smaller effort, however, has successfully extended this foundational work to the demonstration and evaluation of such processes in a natural setting and thus to apply the work to management, conservation and agricultural questions. In this talk, I will share how my laboratory has evaluated fear effects and made modest attempts to demonstrate its importance for patterns in natural settings. Because the literature on the ecology of fear continues to grow exponentially with ever more complicated yet controlled experiments, I will conclude this talk by considering what has been accomplished to date in the primary literature, discussing what methodological approaches can unequivocally show NCE and TMIE signatures in field abundance patterns, sharing how these approaches are being applied in a diversity of systems as well as the challenges experienced and needs for moving forward. This seminar will highlight some of the ways the Kimbro lab is promoting synthesis and consensus on how to move the study of predation risk forward so that it can be rigorously tested in the field and applied to management and conservation challenges. - David Kimbro
Abstract: Evidence for the interplay between ecological and evolutionary processes is increasing, along with recognition of their potential importance for management and conservation. For example, trait divergence and diversity in key consumer and plant species can have far-reaching impacts on community and ecosystem processes, on par in magnitude with the effects of species additions or deletions. Here, I will highlight recent results from my lab of the importance of intraspecific variation in multiple coastal foundation species – seagrasses, salt marsh plants, and oysters – for populations, communities, and ecosystems. I will also provide evidence for a science-practice gap in applying this information to habitat restoration practice, discuss why this gap matters, and outline suggestions for addressing it to enhance restoration success. - Randall Hughes
Professor Russell Bonduriansky
Title: Can sexual conflict resolve the “paradox of sex”?
Abstract: Despite many decades of research, we still do not understand why sexual reproduction is so prevalent in animals. Efforts to resolve this paradox have focused on identifying benefits of sex, but such benefits (e.g. enhanced evolvability) seem to be strongly context-dependent. Indeed, theory suggests that facultative strategies that allow for switching between sexual and asexual reproduction should easily outcompete obligate sexual or asexual strategies. Why are such facultative strategies so rare? Over the past several years, my research group has been exploring a new, fundamentally different solution to this paradox based on sexual conflict. Rather than assuming that sex predominates because it confers benefits, the sexual conflict hypothesis posits that the presence of coercive males acts as a powerful, phylogenetically widespread impediment to the invasion of sexual populations by obligate or facultative asexual strategies, turning sex into an evolutionary trap. I will discuss our theoretical work and experimental findings in facultatively asexual stick insects, and outline preliminary findings from a new study aimed at testing the sexual conflict hypothesis in natural populations.
Professor Shai Meiri
Title: Scales feathers or fur? Babies or eggs? What matters for vertebrate reproduction?
Abstract: Vertebrates take very different routes to reproduction and caring for their young. Broods can be small or large, frequent or infrequent, and of large or small progeny. Some vertebrates lay eggs, some give birth to live young, some care for the eggs, some even care about their offspring – but many do not engage in any form of parental care, and neither warm nor feed their young. It is tempting to explain this immense variation in terms of the deep evolutionary divergence between vertebrate classes. I will try to show, however, that much of the variation occurs within rather than across lineages – and point to lower-bauplane constraints and geography as potential drivers of amniote life history traits.
Title: Sperm in eggs: Social, environmental, and phylogenetic impacts on avian polyspermy
Abstract: In birds normal embryotic development requires the genetic contribution of one sperm, but in addition, the fusing of multiple other sperm with the ovum. This obligate polyspermy means that the failure of enough sperm reaching the ovum can cause early developmental failure. Conversely, too much sperm interacting with the ovum can cause developmental failure due to genetic abnormalities. The number of sperm reaching the egg and trapped in the perivitelline layer, is correlated with avian body size at a broad scale, but does not explain the variation in average number of sperm in similar sized species. Our work has focused on determinants of the quality of sperm that males produce, and the numbers of sperm reaching the egg in three Australian Estrilidids – Zebra, Long-tailed, and Gouldian Finch. We show that variation in sperm numbers on the egg membranes differs across species, but also across pairs within a species. Furthermore both breeding experience with a partner, and breeding success also affect the subsequent quality of sperm, and the number trapped on the egg membranes, providing some insight into the benefits of social partnerships in birds. We also demonstrate that sperm numbers on egg membranes are affected by the genetic structure of a species, and this suggests that sperm/egg interactions may play an important role in limiting hybridisation and speciation processes. Given that hatching failure is an important driver of reproductive success in birds, our results taken together indicate that the dynamics of sperm quality and numbers, as well as the interactions between sperm and both the female reproductive tract and the eggs might determine the extent of successful reproduction. We believe that sperm biology and polyspermy are worthy of further attention, particularly in those management contexts in which reproduction is constrained or compromised in some way.