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Knowing thy own strength dishonesty and intimidation in crayfish

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Knowing thy own strength dishonesty and intimidation in crayfish Powered By Docstoc
					                      Jenny Grigg




    Ecology
     meets
   Physiology

A Symposium to mark the retirement of
   Gordon Grigg: Oct 20-21, 2007
1
                                     Program
                           Saturday 20th October 2007



Session 1   8:50-11:00

8:50    Welcome
        Lyn Beard, Hamish McCallum and Craig Franklin

9:00    ―Test it in the field‖ - a prime Griggian principle
        M.L. Augee

9:10    Dwarfs vs. Giants: Variation in the population ecology of an island macro-
        predator, the Komodo dragon.
        Tim S. Jessop

9:25    Quantifying Aspects of the Evolution of Endothermy
        Peter Brice

9:40    Beyond Groundhog Day: Yearlong Hibernation in a Marsupial Mammal
        Fritz Geiser

9:50    Adaptation in the koala: water and energy
        W. Ellis, A. Melzer and F.N. Carrick

10:05   Feeding ecology of platypuses (Ornithorynchus anatinus) in small
        waterways of south east Queensland
        F.N. Carrick, W. Ellis and A.J. Muscat

10:20   The Natural history of nesting in two Australian freshwater turtles
        David T. Booth

10:35   Histomorphometric changes in the wing bones of the fruit bat, Pteropus
        poliocephalus, (Megachiroptera: Pteropidae) in relation to increased bone
        strain.
        M.B. Bennett and M.R. Forwood


11:00   Morning Tea and Coffee


Session 2   11:30-13:00

11:30   Turning science into conservation outcomes some experiences shared with
        Gordon Grigg
        Bob Beeton




                                           2
11:45   The odyssey of managing feral camels—is there an Achilles Heel?
        Jocelyn Coventry, Glen Edwards, Benxiang Zeng and Kym Schwarztkopf

12:00   Australian (Queensland) Lungfish, Past, Present and Future
        Jean Joss

12:15   A land use ethic provides the courage to kill and eat a national icon
        Dan Lunney

12:30   Effect of Harvesting on the Reproductive Output of Red kangaroos
        Tony Pople

12:45   A devilish dilemma: managing Tasmanian devil disease
        Hamish McCallum and Menna Jones


1300    Lunch


Session 3   14:00-15:30

14:00   Thrills and spills; 45 years of wondering about how critters cope
        Gordon Grigg

14:30   Memes and Mounds: an overview of research into the construction
        behaviour and colony physiology of a minor celebrity insect in northern
        Australia
        Peter M. Jacklyn

14:40   Program for Planned Biodiversity ( PPBio ): measuring and monitoring the
        impacts of climate change.
        Jean-Marc Hero

14:55   Has Historical Land Clearing Impacted Australia’s Climate?
        Clive A. McAlpine, Jozef Syktus, Ravinesh C. Deo, Peter J. Lawrence,
        Hamish A. McGowan and Stuart R. Phinn

15:10   Old age, bad backs, and cane toads
        Rick Shine, Cathy Shilton and Greg Brown1


Session 4   16:00-17:30

16:00   The fish that wouldn’t drown: On the adrenergic life of lungfishes
        Stefan Nilsson

16:15   Air-breathing organs of adult Atlantic tarpon Megalops atlanticus at sea
        Roger S. Seymour




                                        3
16:25   Effect of aerial O2 partial pressure on bimodal gas exchange and air-
        breathing behaviour in Trichogaster leeri
        Lesley A. Alton, Craig R. White and Roger S. Seymour

16:40   Predicting the diving behaviour of the bimodally respiring Arafura Filesnake
        Kirstin L. Pratt, Robbie S. Wilson, Simon Blomberg and Craig E. Franklin

16:55   Diving behaviour in two distinct populations of gravid flatback turtles
        (Natator depressus)
        Jannie B. Sperling

17:10   Adaptation and Survival of early PhD students in the Paleozoic era at
        Sydney University
        Gillian P. Courtice, Jane Thompson and Eric van Beurden

17:25   Lounge Lizards – When Science Informs Pet-keeping
        David S Kirshner



18:00   Drinks and Dinner in the Great Court




                                         4
                           Sunday 21st October 2007


Session 5    9:30-11:00

9:30    Changes in the amphibian gut during larval development and metamorphosis
        Susanne Holmgren and Monika Sundqvist

9:45    The possible role of membrane lipids in the exceptionally long life of echidnas
        A. J. Hulbert , Lyn Beard and Gordon Grigg

10:00   Physiological responses and refuge utilisation by the intertidal predatory
        whelk, Morula marginalba
        Melissa K. Langridge, Craig E. Franklin and Gregory A. Skilleter

10:15   The effect of prolonged aestivation on metabolic enzyme activities in
        muscle and liver from the Green-striped burrowing frog
        Beth L. Symonds, N.J. Hudson, Helga Guderley, and Craig E. Franklin

10:30   Citrate synthase activity does not account for age-related differences in
        maximum aerobic performance in House Sparrows (Passer domesticus).
        William A. Buttemer, Claus Bech, and Mark A. Chappell

10:40   Cooler temperatures increase sensitivity to ultraviolet B radiation in
        embryos and larvae of the frog Limnodynastes peronii
        Vincent O. van Uitregt, Robbie S. Wilson and Craig E. Franklin


11:00   Morning Tea and Coffee


Session 6    11:30-13:00

11:30   Allosteric modulation of haemoglobin function in response to changes in
        oxygen supply and demand: insights from aquatic ectotherms
        Rufus M.G. Wells

12:00       TBA


12:30   Tracking Crocodiles using telemetry
        Craig Franklin & Mark Read

12:50   Closing Remarks
        Open Floor




                                         5
                 ―Test it in the field‖ - a prime Griggian principle

                                    M.L. Augee

             Wellington Caves Fossil Studies Center, Wellington NSW

Gordon has always insisted that a true understanding of animal behaviour and
physiology cannot be gained by laboratory and captive studies alone but need to be
tested and observed in the field. An example of the application of this principle is
seen in studies carried out in the 1980s on hibernation in echidnas. Previous studies
of captive echidnas and results of physiological studies caused me to conclude that
echidnas were not hibernators. Gordon doubted this, and radio-tracking studies in the
Snowy Mountains showed that echidnas are indeed hibernators in the true
mammalian sense of the word.




                                         6
  Dwarfs vs. Giants: Variation in the population ecology of an island macro-
                       predator, the Komodo dragon.

                                    Tim S. Jessop1
  1
      Department of Wildlife Conservation and Science, Zoos Victoria, Parkville 3052,
                                        Australia.


Across islands, shifts in maximal body size of populations represent a conspicuous
means by which individual animals often reconcile local forage/prey availability. A
reduction in body size is intuitively associated with decreased absolute energetic
requirements. Scaling relationships between body size and energetic requirements
have important implications for the demography of populations. For example, the
energetic equivalence rule, suggests an inverse relationship between body size and
population abundance. Here I examined the interaction between prey availability,
maximal body size and ensuing demographic differences (via density estimates and
population growth rates) among four island populations of the Komodo dragon.
Despite large differences in maximal body size among four islands, there was no
evidence for even partial demographic compensation (via population: abundance and
growth rate) with decreased body size. Rather body size was positively correlated
with both population density and population growth rate. This relationship has
important management implications for Komodo dragons. Particularly, as it suggests
that dwarf dragon populations persisting on prey poor small islands, currently exhibit
demographic tendencies (eg. Allee effects) that could decrease their population
viability.




                                            7
               Quantifying Aspects of the Evolution of Endothermy

                                      Peter Brice

        School of Integrative Biology, The University of Queensland, Qld 4072

Endothermy has evolved independently in at least two clades of vertebrates. Various
models have been proposed to explain this evolution. Such models are often
conceptual or qualitative. Quantitative analysis of some of these may provide insight
into their feasibility, or at least highlight important aspects of them.
        In this study, a recent framework for the stepwise evolution of endothermy was
used as the basis of some initial quantitative modelling. Specifically, this modelling
demonstrated a progression of possible stages whereby a 4 kg animal with reptilian
standard metabolic rate, SMR, thermal conductance, Ko, and ventilation rate, Vi,
evolved into one with mammalian basal metabolic rate, BMR, K o and Vi in an
environment where operative temperature, Te, varied daily between 15 and 45 oC. In
this scenario, stages were usually accompanied by measurable benefits in terms of
time spent within various ranges of preferred body temperature, T pref.
        Crucial to this simulation was the initial ―evolution‖ of mammalian values of K o.
Then, limiting aerobic scope, the maximum metabolic rate as a multiple of SMR,
allowed the accrual of advantages derived from incremental increases in
thermogenesis and SMR until a fully homeothermic endotherm with a thermoneutral
zone and a comparatively high BMR ―evolved‖. During this transitional sequence a
pattern reminiscent of daily torpor in a heterothermic endotherm emerged showing
how torpor may be plesiomorphic, or at least present in early proto-endotherms.
        Quantitative modelling such as this highlights costs and benefits in the
evolution of endothermy and provides the basis for further speculation. For example,
in this study, respiratory evaporative heat loss was shown to be substantial without
the benefit of turbinal scrolls even in this warm, presumably moist environment.
Further modelling would allow the quantification of benefits accrued by these and
other adaptations to endothermy in a wide range of environments as well as the
investigation of other salient features such as body size and climate in the evolution
of endothermy.




                                            8
    Beyond Groundhog Day: Yearlong Hibernation in a Marsupial Mammal

                                    Fritz Geiser

 Zoology, University of New England, Armidale 2351, Australia, fgeiser@une.edu.au

Many mammals hibernate each year for about six months in autumn and winter and
are active and reproduce during spring and summer. Eastern pygmy-possums
(Cercartetus nanus), opportunistic non-seasonal hibernators with a capacity for
substantial fattening, were used to investigate whether they differ from the usual
pattern and would continue to hibernate beyond winter. The time they were able to
hibernate without access to food before their body fat stores were depleted was also
determined. Pygmy-possums exhibited a prolonged hibernation season lasting on
average for 310 days. The longest hibernation season in one individual lasted for 367
days. For much of this time, despite periodic arousals after torpor bouts of ~12.5
days, energy expenditure was reduced to only ~2.5% of that predicted for active
individuals. These observations represent the first report on body fat-fuelled
hibernation of up to an entire year and provide further evidence that prolonged
hibernation is not restricted to placental mammals living in the cold. The long
hibernation season suggests that either a large safety margin was favoured by
natural selection in response to unpredictability of weather and food availability in
Australia, or that it is a remnant from the last ice age (Naturwissenschaften 2007).




                                         9
                     Adaptation in the koala: water and energy

                        W. Ellis1, A. Melzer2 and F.N. Carrick3
  2
   Koala Research Centre of Central Queensland, Central Queensland University,
                              Rockhampton, Qld
1
 Conservation, Research Endangered Species, Zoological Society of San Diego, San
                                  Diego, USA
     3
       Koala Study Program, The University of Queensland, St Lucia 4072 Qld

Recent work has described the behavioural responses of koalas to warmer
conditions and predicted bioclimatic limits to the northern range of this species. We
studied two groups of koalas during a drought in central Queensland to investigate
potential impacts of climatic variability on this species. We tested the hypotheses that
1) water turnover of koalas would be positively correlated with leaf moisture of
browse and 2) that, in a semi-arid environment, koalas preferentially select browse
species with high percent leaf moisture. Although there was a trend for water
turnover to correlate positively with leaf moisture of selected browse, increases in leaf
moisture of diet species did not correspond to proportional increases in the
occurrence of these species in the diet of koalas. Leaf moisture may influence tree
selection during periods of extremely high or low temperature, but other physical
attributes, such as shade, of trees appear to be important to roost selection by
koalas.




                                           10
 Feeding ecology of platypuses (Ornithorynchus anatinus) in small waterways
                          of south east Queensland

                        F.N. Carrick, W. Ellis and A.J. Muscat

     School of Integrative Biology, The University of Queensland, St Lucia 4072

While iconic, visible and frequently encountered wildlife may gain recognition in
urban planning schemes, the conservation of more enigmatic species poses a
paradox to conservation. There is no evidence that better conservation outcomes
follow a species’ profile, but logic predicts that the disappearance of invisible species
may be harder to document, let alone reverse. The platypus is an enigmatic but
widespread species, occurring in a limited range of aquatic environments across
south east Queensland. It persists in some of the highly modified urban waterway
system, but is absent elsewhere. We undertook to examine the feeding habits and
distribution of platypus within this system. The higher abundance of prey items such
as insects and crustaceans in creeks of relatively higher water quality appeared to be
critical to the presence of platypus in the waterways of south east Queensland.
Decapods and odonatans dominated the contents of platypus cheek pouches during
this study and there was a positive correlation between the occurrences of these
particular prey types and the presence of platypus at sites. Platypus were found in
the less disturbed and naturally vegetated elements of the creek system.




                                           11
       The Natural history of nesting in two Australian freshwater turtles

                                  David T. Booth

  School of Integrative Biology, The University of Queensland, Qld 4072, Australia

Two species of freshwater turtle, the Brisbane river turtle Emydura signata, and the
broad-shelled river turtle Chelodina expansa nest seasonally adjacent to the lakes on
The University of Queensland’s St Lucia campus. Over 10 years multiple nesting
events for both species were observed. C. expansa nested between March and
September, while E. signata nested between October and February. Both species
were only ever observed nesting during or immediately after rain. Both species
exhibited stereotypic chelonian nesting behaviour, i.e. the nests were always
constructed by alternate scooping movements of the back legs, and nests dug to the
maximum depth possible by the out stretched hind limb. However the specific details
differed between the two species. C. expansa was only ever observed constructing
nests during daylight hours, and always nested a considerable distance from the
waters’ edge typically 50-300 m, and usually on top of a hill. C. expansa was
remarkably tolerant of people during the nest construction and egg laying process,
frequently nesting close to pathways with heavy pedestrian traffic. In contrast, E.
signata nested predominatly at night observed nesting at night, but some individuals
nested during the day, and if nesting during the day preferred the late afternoon -
early evening period. E. signata always constructed their nests within 50 m of the
water, most frequently with 20 m of the water’s edge and were very easily disturbed
by pedestrians during the nest construction process, i.e. they invariable abandoned
their nesting attempt if a pedestrian was closer than ~15 m during the nest
construction process.




                                         12
    Histomorphometric changes in the wing bones of the fruit bat, Pteropus
   poliocephalus, (Megachiroptera: Pteropidae) in relation to increased bone
                                    strain.

                         M.B. Bennett1 and M.R. Forwood1
      1
      School of Biomedical Sciences, The University of Queensland, St. Lucia,
                           Queensland, Australia. 4072

Fluorochrome labelling of bone formation was used to examine the effect of exercise
(flight) on the wing skeleton of fruit bats, Pteropus poliocephalus, over a 194 day
period. The bats in this study had been born and raised in captivity and it was
hypothesised that the large increases in bone strain that accompanied active flight
would result in bone formation at the periosteal bone surface, leading to increased
mechanical stiffness and strength. This hypothesis was not supported by the results.
Bone formation rates, percentage mineralising surface and mineral apposition rates
at the mid-shaft periosteal surface of the radius, metacarpal III and metacarpal V
were small. The proximal phalanx of digit V did not display any bone formation at
this surface. Bone appositional activity was not significantly different between
baseline, control (non-flight) and treatment (flight) groups at any time-point of the
experiment. Apposition, although limited, occurred primarily at the endocortical
surface in all bones of all animals. No correlation was found between activity and
bone formation. Active intracortical remodelling (a total of four secondary osteons)
was only seen in three individuals. There was evidence of earlier remodelling activity
in most bones, although there was no evidence of any secondary remodelling in the
proximal phalanx.




                                         13
Turning science into conservation outcomes some experiences shared with
                              Gordon Grigg

                              Bob Beeton

                   The University of Queensland




                                   14
         The odyssey of managing feral camels—is there an Achilles Heel?

     Jocelyn Coventry1, Glen Edwards2, Benxiang Zeng2 and Kym Schwarztkopf2
     1
      Department of Primary Industry, Fisheries and Mines, Alice Springs NT 0870
2
    Department of Natural Resources, Environment and The Arts & Desert Knowledge
                Cooperative Research Centre, Alice Springs NT 0870

Australia supports the largest free-ranging population of one-humped camels
(Camelus dromedarius) in the world. The species was introduced to Australia in the
mid 1800’s for transport and haulage purposes. However, with improvements in
mechanised transport, reliance on the camel declined and many camels were turned
out to establish feral populations. Current estimates put the population of feral
camels in Australia at around one million with the population doubling every eight
years. As the population of feral camels increases, so too does their degree of impact
on desert ecology, cultural values and human enterprise. In this monograph, we
explore aspects of the feral camel’s physiology, behaviour and anatomy which, while
having allowed the species to thrive in the often harsh and dry desert regions of
Australia, could potentially be exploited to manage the species and its impacts
across remote, arid Australia.




                                         15
            Australian (Queensland) Lungfish, Past, Present and Future

                                      Jean Joss
   1
       Department of Biological Sciences, Macquarie University, Sydney, NSW 2109

Lungfish (Dipnoi) first appear in the fossil record in the Early Devonian. During the
Devonian they are abundant and represented by several different lineages but by the
Carboniferous, there numbers are reduced and they have mostly settled into the
general morphological pattern that is represented today by the three living genera.
Neoceratodus, the Australian or Queensland lungfish, itself is thought to have
changed very little as a species (N forsteri) since the Cretaceous. The conservative
form and declining numbers of lungfish since the Devonian correlates with an
increase in cell size which has been interpreted as an increase in genome, a fact
corroborated by the very large genome size of living lungfish. In turn, a large
genome (cell size) correlates with neoteny in families of urodele amphibians and I
would say lungfish as well. This makes the living lungfish, and in particular N forsteri,
an excellent model for looking at developmental characteristics that can inform us
about the mechanisms of evolution that produced the first tetrapods. However, just
as this goldmine of information is beginning to provide us with some tantalizing clues,
the future of our lungfish is being threatened by politics and climate change, What
can we do?




                                           16
       A land use ethic provides the courage to kill and eat a national icon

                                   Dan Lunney1
 1
     Department of Environment and Climate Change, PO Box 1967, Hurstville NSW
                     2220 dan.lunney@environment.nsw.gov.au

―Sheep replacement therapy‖ is arguably the most enduring epigrammatic phrase
that Gordon Grigg has uttered in his working lifetime. Grigg has a consuming passion
with kangaroos. He has applied a land use ethic to a detailed working knowledge of
kangaroos and derived an ecologically robust approach to utilizing kangaroos instead
of running sheep on the ever-degrading rangelands. So, kangaroos are the sheep
replacement therapy for this over-used landscape. In 1987, Grigg presented talk at a
wildlife forum run by the Royal Zoological Society of NSW. The newly-appointed
editor of the society’s journal, Australian Zoologist, thought that the wider
membership of the Society, and beyond, wanted to hear the story in detail. The
impact was immediate, and in 1988 the Society organised a full-day forum on the
subject. Grigg was the centre-point; he was neither alone in that view, nor was he
unopposed. That divide still prevails. That 1988 forum remains as a turning point in
the debate over the matter of eating kangaroos as a basis for management. In 1994,
Gordon Grigg, now at UQ, organised a 3-day conference on the sustainable use of
wildlife, including kangaroos. It was published in 1995, and it remains as a
cornerstone in the subsequent debate. In 2000, the Royal Zoological Society ran a
forum seeking a zoological revolution, and Grigg’s paper is a masterful summary of
the value of utilizing kangaroos. Others following his pioneering effort, such as
Archer’s and Beale’s Going Native in 2004, appreciate Grigg’s leadership. Gordon
Grigg remains as not only a zoologist of perception, but also one of courage in
applying his findings to conserving our land and our fauna.




                                        17
Effect of Harvesting on the Reproductive Output of Red kangaroos

                          Tony Pople

                  Department Primary Industries




                               18
              A devilish dilemma: managing Tasmanian devil disease

                        Hamish McCallum1 and Menna Jones1
    1
        School of Zoology, the University of Tasmania, Private Bag 5, Hobart 7001

As the largest surviving marsupial carnivore, the Tasmanian devil is an iconic
species. A disfiguring and invariably fatal facial cancer, first reported in 1996, has
now spread across most of the range of the devil, leading to population declines of
up to 90% and a prognosis of likely extinction in 15-20 years. Transmission
experiments have confirmed that the cancer is infectious and genetic evidence
strongly suggests that it is a transmissible cell line. Based on this problem, we
present a decision tree for handling emerging diseases in wildlife, emphasising steps
that should be taken before the disease can be identified and a vaccine or treatment
can be developed. Captive ―insurance‖ populations have already been established
and establishing free-ranging disease-free populations on offshore islands is now
being investigated. A disease suppression trial, in which all infected animals
captured are removed, is in progress on the Tasman Peninsula, which is connected
to the mainland Tasmania only by a single bridge. A simple model, parameterized
using the unmanipulated population on the Freycinet Peninsula, suggests that
approximately 60% of diseased animals need to be removed three months to
eliminate the disease. However, this proportion is strongly dependent on the
incubation period of the disease, which is poorly known. More than 130 diseased
devils have been removed in the trial to date. This removal program has influenced
the progression of the tumor epidemic. The stage structure of the tumor population
has changed, with fewer large tumors now being found. There are indications that the
spatial spread and increase in prevalence through time have been slowed, relative to
the unmanipulated population on the Freycinet Peninsula. Encouragingly, transitions
from healthy to diseased state have peaked and are now declining. Nevertheless, it
remains unclear whether this disease suppression trial will be successful.




                                          19
Thrills and spills; 45 years of wondering about how critters cope


                          Gordon Grigg

    School of Integrative Biology, the University of Queensland




                                20
   Memes and Mounds: an overview of research into the construction
        behaviour and colony physiology of a minor celebrity insect in
                             northern Australia

                                  Peter M. Jacklyn1
        1
         Tropical Savannas Cooperative Research Centre, Darwin, NT 0909

People have speculated about the striking, precisely aligned ―magnetic‖ mounds built
by termites of the genus Amitermes in northern Australia for a very long time, with the
first written accounts dating to the late 19th century, yet it wasn’t until Gordon Grigg
rotated mounds and systematically measured their orientations in the 1970s that any
substantial research was carried out to test these speculations. The ideas Gordon
then developed about the advantages offered by this remarkable architecture proved
insightful and have shaped the subsequent thinking on the physiological function of
these mounds. This talk reviews the concepts and research that have developed
around this small but fascinating area of investigation.




                                          21
  Program for Planned Biodiversity ( PPBio ): measuring and monitoring the
                        impacts of climate change.

                                 Jean-Marc Hero

 The Centre for Innovative Conservation Strategies, School of Environment, Griffith
         University,PMB 50, Gold Coast Mail Centre, Qld 9222, Australia

The Centre for Innovative Conservation Strategies (CICS) at Griffith
University has initiated a new ―Program for Planned Biodiversity Studies‖ (PPBio) in
Australasia. A research platform for collecting, storing & sharing biological
information for long-term ecosystem condition assessment. The program was
developed in Brasil by Bill Magnusson (an old colleague of Gordon's) to facilitate
long-term regional biodiversity monitoring and condition assessment. PPBio involves
integrated, standardised long-term ecological plots based on a 5km x 5km grid of
trails, with 30 permanent terrestrial plots (250m long) and any number of permanent
aquatic plots (depending on available water courses, etc.). The modular design
allows for modifications of the standard grid and in 2006 we established the first
Australian grid at Karawatha Forest within the peri-urban zone of outer Brisbane,
south-east. Our first result examine vegetation composition and abundance which
varied greatly among plots demonstrating the spatial heterogeneity of eucalypt
woodlands and the importance of meso-scale approach for biodiversity research and
condition assessment. Future research will incorporate the Grigg acoustic
identification technology. These data provide an essential baseline for reserve
managers to monitor colonisation and extinction patterns in response to threats such
as fire, human disturbance and climate change.




                                        22
          Has Historical Land Clearing Impacted Australia’s Climate?

     Clive A. McAlpine1, Jozef Syktus2, Ravinesh C. Deo1, Peter J. Lawrence3,
                   Hamish A. McGowan1 and Stuart R. Phinn1
      1
       Centre for Remote Sensing and Spatial Information Sciences, School of
  Geography, Planning and Architecture, The University of Queensland, Brisbane,
                                   Australia 4072
    2
      Queensland Climate Change Center of Excellence, Department of Natural
   Resources and Water, 80 Meiers Rd, Indooroopilly, Brisbane, Australia 4068
    3
      Cooperative Institute for Research in Environmental Science, University of
                         Colorado, Boulder, Colorado 80309

The Australian landscape has been extensively cleared since European settlement.
However, the potential impact of historical clearing on regional climate has been a
secondary consideration in the climate change projections and policies. We
conducted a climate model sensitivity simulations to quantify changes in regional
climate by comparing results from pre-European and modern-day land cover
characteristics. The results of the sensitivity simulations showed the following: a
statistically significant warming of the surface temperature, especially for summer in
eastern Australia (0.4-2C) and southwest Western Australia (0.4-0.8C); a
statistically significant decrease in summer rainfall in southeast Australia; and
increased surface temperature in eastern regions during the 2002/2003 El Niño
drought event. The simulated magnitude and pattern of change indicates that LCC
has potentially been an important contributing factor to the observed changes in
regional climate of Australia.




                                         23
                         Old age, bad backs, and cane toads

                      Rick Shine, Cathy Shilton and Greg Brown1
          1
              School of Biological Sciences, University of Sydney, NSW 2006

Invasion can be back-breaking work. Spare a thought for the cane toad, a frog of the
Brazilian rainforest that has been translocated to Australia, and has somehow
managed to colonise much of the driest continent on earth. Radiotracking shows that
the rate of toad invasion has accelerated through time; invasion-front toads now
move amazing distances every night during the wet-season. This behaviour poses
massive challenges to an anuran body plan not designed for rapid and sustained
locomotor activity. In the talk, I will outline our recent results on how the invasion
process has affected the well-being of toads in Australia, and identify unsuspected
convergences between Professor Grigg and his beloved toads.




                                          24
         The fish that wouldn’t drown: On the adrenergic life of lungfishes

                                   Stefan Nilsson1
1
    Department of Zoophysiology, Göteborg University, Box 463, SE 405 30 Göteborg,
                                      Sweden

There are currently three extant genera of true lungfish (dipnoans): one in South
America (Lepidosiren), one in Africa (Protopterus) and one in Australia
(Neoceratodus). Although there are numerous fish that can breathe air, a common
feature of the dipnoans is a vascular arrangement with a pulmonary artery, and a
pulmonary vein that brings the oxygenated blood directly to the atrium. Although it
would appear terribly embarrassing to any fish, the South American and African
lungfish may, in fact, drown if prevented from surfacing for air. Not so the Australian
lungfish, which has a much better gill structure and will surface for air as needed.
The control systems regulating the blood flow in the dipnoan circulation are still not
well known. In most vertebrates, adrenergic systems – circulating catecholamines
and adrenergic nerves (postganglionic neurons of the sympathetic nervous system) –
play essential roles in the control of both cardiac function and vascular resistance. In
lungfish (Protopterus), a sympathetic nervous system was not described until 1950
by W. Holmes and, indeed, our own work point to relatively undeveloped sympathetic
chains in lungfish. Furthermore, search for adrenergic nerve fibres in both
Lepidosiren and Protopterus using histochemical techniques have failed to provide
solid evidence for such fibres. Instead, there is an impressive presence of chromaffin
cells within the atrium of the heart and – at least in Protopterus – also in the walls of
the left posterior cardinal vein (azygos vein) and the intercostals arteries. A
cholinergic innervation of the lung, the heart and possible some vascular segments
has been demonstrated in Lepidosiren and Protopterus, but any antagonistic
adrenergic control is likely to be due to locally released (―paracrine‖) or circulating
catecholamines from the chromaffin stores in the heart and vascular walls.




                                           25
    Air-breathing organs of adult Atlantic tarpon Megalops atlanticus at sea

                                 Roger S. Seymour

               Ecology & Evolutionary Biology, University of Adelaide

Gordon Grigg was first to show that the evolution of air-breathing organs (ABO) is
associated not only with hypoxic environments, but also with activity. Most air-
breathing fish occupy fresh or brackish waters where hypoxia is common. Juvenile
Pacific tarpon Megalops cyprinoides, from rivers and billabongs in northern Australia,
use a modified swimbladder ABO to augment aerial oxygen uptake in response to
hypoxia and exercise. However, adult tarpon migrate to the ocean, where hypoxia is
uncommon in the surface waters, yet anecdotal reports indicate that air-breathing
persists. Thus tarpon are unique among teleosts in being the only air-breathing
species in the pelagic marine environment. This allometric study of the ABO
anatomy of large Atlantic tarpon M. atlanticus indicates that the ABO remains fully
functional in fish weighing up to 39 kg. Mass of the ABO (g) scales isometrically with
body mass (kg) according to: MABO = 4.97Mb0.996. Function is maintained probably to
support high levels of aerobic activity in this well known sport fish, rather than as a
response to hypoxia.




                                          26
Effect of aerial O2 partial pressure on bimodal gas exchange and air-breathing
                          behaviour in Trichogaster leeri

             Lesley A. Alton1, Craig R. White1,2 and Roger S. Seymour1
1
    Environmental Biology, School of Earth and Environmental Sciences, University of
                  Adelaide, Adelaide, South Australia, 5005, Australia,
    2
      School of Biosciences, University of Birmingham, Edgbaston, Birmingham, B15
                                        2TT, UK


The effects of experimental alterations of aerial O 2 partial pressure (PO2air) on
bimodal gas exchange and air-breathing behaviour were investigated in the aquatic
air-breathing fish Trichogaster leeri in normoxic water. Fish responded to increasing
PO2air by decreasing air-breathing frequency, increasing aerial O2 consumption rate
   .
(VO2), increasing mean O2 uptake per breath (VO2/breath), and decreasing aquatic
 .                                .
VO2 to maintain a constant total VO2. The rate of oxygen uptake from the ABO during
           .
apnoea (VO2ap) was derived on a breath-by-breath basis, from VO2/breath and
                    .
apnoea duration. VO2ap and estimates of ABO volume were used to calculate the PO2
in the ABO at the end of apnoea. This increased with increasing PO2air, suggesting
that ABO-PO2 is not regulated at a constant level by internal chemoreceptors.
                        .
Furthermore, mean VO2ap increased with increasing PO2air, indicating that the
observed increase in VO2/breath with increasing PO2air was facilitated not only by an
increase in apnoea duration, but also by an increase in the air-blood PO2 gradient.




                                         27
 Predicting the diving behaviour of the bimodally respiring Arafura Filesnake

    Kirstin L. Pratt1, Robbie S. Wilson1, Simon Blomberg1 and Craig E. Franklin1
         1
             School of Integrative Biology, University of Queensland, Australia


The majority of vertebrate diving literature uses the calculated ADL (cADL) equation
to predict dive times, however many studies demonstrate this is an underestimation
of empirical dive times. The current study uses the fully-aquatic Arafura filesnake to
test the fundamental relationship between oxygen consumption and dive time over a
wide range of metabolic states induced through digestion. Filesnakes were fed a
meal of varying size (0 – 15% of body mass) and both diving behaviour and VO2
measured. Digestion elevated VO2 to 12 times mean fasted values with the largest
meal size. There was a significant relationship between meal size and VO2 however
dive durations were significantly longer than predicted by the cADL. A. arafurae was
found to utilise aquatic respiration with extraction efficiency decreasing with
increasing meal size. Increases in oxygen storage capacity and the utilisation of
aquatic respiration are possible explanations for extended dive durations.




                                            28
Diving behaviour in two distinct populations of gravid flatback turtles (Natator
                                  depressus)

                                 Jannie B. Sperling1
     1
         School of Life Sciences, University of Queensland, Brisbane, Queensland

This paper presents the first data on the diving behaviour of flatback sea turtles
(Natator depressus) between nesting events. Dive profiles were recorded in turtles
from two genetically distinct breeding populations, around Curtis Island in
Queensland and around Bare Sand Island in the Northern Territory, using Time-
Depth Recorders (TDRs). The turtles dived routinely for longer than other large sea
turtles, up to 98 min. Like other sea turtles, flatbacks spent most of the time at depth,
with little time (10% ±4% SD) at or near the surface. Several dive types were
identified, most of which could be referenced to terminology developed for other sea
turtles. Dive type 1 comprises a quick decent, a long bottom phase and a quick
ascent. Dive type 2 comprises a descent, followed immediately by an ascent. Dive
types 3 and 4, as described by previous authors, resolve into four different dive types
in flatbacks, all with a gradual ascent phase presumed to be caused by a slow
increase in buoyancy. Dive type 5 is a short shallow dive associated with near-
surface activity. 57% of the dive-time was spent engaged in dive type 1 with an
apparent inactive bottom reflecting the tidal cycle. It was the longest of the dive
types, in average 50 min (±9 min SD). At both locations, dive type 1 occurred more
commonly by day, by an average of 14%. Dive type 1 was also most prevalent in the
middle third of the internesting interval in most turtles, while the eggs were maturing.
Dive types 2, 3 and 5 were uncommon in both populations. The turtles dived to
maximum depths of 29 m and 44 m at Curtis Island and Bare Sand Island,
respectively.




                                           29
 Adaptation and Survival of early PhD students in the Paleozoic era at Sydney
                                   University

           Gillian P. Courtice1, Jane Thompson2 and Eric van Beurden3
 1
  Curlew Biological Services, PO Box 67 Pacific Palms NSW 2428, 2Women's and
  Childrens Health, The Canberra Hospital, PO Box 11 Woden ACT 2606, 3Health
Promotion Unit, Population Health Planning & Performance Directorate, North Coast
               Area Health Service PO Box 498 Lismore NSW 2480


Gordon’s first postgraduate students emerged at the end of his Devonian period,
moving into the Carboniferous with the emergence of amphibian studies. This era
was marked by extensive frogging expeditions, when Litoria aurea was thick on the
ground and Litoria flavipunctata called in the New England swamps. Water holding
frogs were unceremoniously dug up from the receding rainforests. Early reptilian
studies by students were overtaken at the beginning of the Gordon Mesozoic in a
massive adaptive radiation, into crocodiles, flying, radiotelemetry, termites,
kangaroos, some of the best adapted lasting for eons. Wonderful outback odesseys
marked the early era and the diverse environment laid the foundation for emergence
of the young and their survival into the Quaternary and the age of man ahead of their
master.




                                         30
             Lounge Lizards – When Science Informs Pet-keeping

                               Dr David S Kirshner

A pair of captive lace monitors housed indoors under controlled conditions has
shown a number of interesting behaviours associated with reproduction. As the
monitors are housed in the author’s home and habituated to the continual presence
of humans, some breeding and nesting behaviours were documented that would
normally go unnoticed in captives held outdoors or in wild individuals.




                                       31
 Changes in the amphibian gut during larval development and metamorphosis

                    Susanne Holmgren1 and Monika Sundqvist1
      1
       Department of Zoophysiology, Göteborg University, Göteborg, Sweden

The gut of anuran amphibians develops in two phases. The gastrointestinal canal is
first formed prior to and around the onset of exogenous feeding, but is extensively
remodeled during metamorphosis. At this stage the frog also changes from
herbivorous to carnivorous feeding. Our studies have investigated how the enteric
nervous system (ENS; the nervous system of the gut) develops and changes during
these two phases, using Xenopus laevis as experimental animal. In Xenopus, the
stomach develops to a thick-walled reservoir with oxyntico-peptic cells at
metamorphosis, while the intestine is shortened to ca 25 % of its previous length.
Irregular, segmental contractions in the gut start at developmental stage 41 and
develop into regular contraction waves (stage 43) well before the onset of exogenous
feeding at stage 45. Methods: Gut motility during these early stages, when the larvae
are transparent, was recorded using video microscopy, and drugs were added to the
whole anaesthetized larva. Gut muscle from specimen around metamorphosis were
studied as ring preparations in organ baths. Immunohistochemistry or semi-
quantitative PCR was used to detect the presence of neurotransmitters,
neurotrophins (NTs) and NT receptors. NTs are important for the development and
sustenance of the ENS. Results: Most of the NTs (NT-4, BDNF and NGF) as well as
the p75NTR receptor were present at all stages investigated. In contrast, the number
of nerve fibres showing immunoreactivity for a Trk-like NT receptor, as well as mRNA
expression for NT-3 were high early in development, low at stage 54, but increased
again at metamorphosis. Addition of drugs to the larvae showed that functional
receptors for acetylcholine, neurokinin A, VIP, adenosine and a response to nitric
oxide are present from stage 43, while an endogenous cholinergic tonus appears at
stage 45. At metamorphosis, several changes in the control of both stomach and
intestinal motility occur. In the stomach a nitrergic tone develops, a 5-HT receptor
involved in muscle contraction is expressed, and the mechanisms of action of UTP
change. In the intestine, an inhibitory purinergic mechanism develops. In conclusion:
Gut motility and its nervous control are well developed before the onset of exogenous
feeding. Several changes occur during metamorphosis; these may be part of an
adaptation from an herbivorous suspension diet to solid, carnivorous food. Our
results also suggest that among the neurotrophins, NT-3 in particular is important for
metamorphosis in Xenopus laevis.




                                         32
                    The possible role of membrane lipids in the
                        exceptionally long life of echidnas

                    A. J. Hulbert1 , Lyn Beard2 and Gordon Grigg2
1                                                                                     2
    School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522
                 School of Integrative Biology, University of Queensland

The echidna (Tachyglossus aculeatus) is an exceptionally long-living mammal having
a maximal lifespan of ~50 years. This is four-to-five times that predicted from its body
mass and consequently it’s longevity quotient is 4-5. This longevity quotient is similar
to two other exceptionally long-living mammalian species; the naked mole-rat
(Heterocephalus glaber) and Homo sapiens. In recent times, the types of fats that
make up cellular membrane have been implicated in the determination of a species
maximum lifespan. This modification of the oxidative stress theory of aging, which
has been called the membrane pacemaker theory of aging, emphasises the fact that
polyunsaturated fats are very susceptible to lipid peroxidation but monounsaturated
fats are resistant to peroxidation. As a test of this theory, we have measured the fatty
acid composition of membrane lipids isolated from tissues of echidnas. We have
found that like the other long-living mammals mentioned above that echidna
membranes are more monounsaturated and less polyunsaturated than you would
predict from their body size but are you would predict from their maximum longevity.




                                          33
   Physiological responses and refuge utilisation by the intertidal predatory
                         whelk, Morula marginalba

        Melissa K. Langridge1, Craig E. Franklin1 and Gregory A. Skilleter1

    1 School of Integrative Biology, Faculty of Biological and Chemical Sciences,
         University of Queensland, Brisbane, Queensland 4072, Australia

Rocky intertidal regions are model systems for examining the role of climate on
communities as the ecology of intertidal organisms is closely linked to physical
factors along vertical and horizontal gradients of the shore. We characterised the
microclimates experienced by the predatory whelk, Morula marginalba, and used an
integrated ecological and physiological approach to determine how their: (1)
distribution and abundance, (2) utilisation of refuges (rock pools and crevices), and
(3) thermal sensitivity (measured by metabolic response and tenacity) varies along
gradients of thermal stress. In all microhabitats, substratum temperatures were more
variable and maximal temperatures were greater higher on the shore than further
down. Crevices and pools provided less thermally variable microhabitats to the
whelks, where maximal temperatures were 5°C – 10°C less than on exposed rock.
Whelks were less abundant and utilised refuges in greater proportions where thermal
stress was greater higher on the shore and in locations sheltered from wave splash.
Although whelks were able to lower their level of metabolism to cope with long-term
increases in temperature, physiological function was severely compromised when
body temperatures exceeded 40°C. Refuges were thus essential to M. marginalba to
avoid sublethal or lethal thermal stress where temperatures on exposed surfaces
exceeded 50°C high on the shore. Refuges play an important role in the ecology and
thermal physiology of organisms living on rocky shores and may act as buffers
against climate-related stress as extremes in temperatures and storms become more
frequent in the future.




                                         34
 The effect of prolonged aestivation on metabolic enzyme activities in muscle
   and liver from the Green-striped burrowing frog (Cyclorana alboguttata)

 Beth L. Symonds,1 Nicholas J. Hudson1, Helga Guderley2, and Craig E. Franklin1
  1
    School of Integrative Biology, University of Queensland, St Lucia, Queensland,
                                    Australia 4072
  2
    Departement de Biologie, Universite Laval, Quebec, Quebec, Canada, G1K 7P4

Green-striped burrowing frogs (Cyclorana alboguttata) depress their metabolism by
up to 70% of resting metabolic rate during prolonged aestivation. The ATP demand
of skeletal muscle is a large contributor to C. alboguttata’s overall energy
requirement, and plays an important role in the coordinated down-regulation of
metabolic processes during aestivation. However, upon awakening from aestivation
C. alboguttata must be able to return to an active locomotor state to allow excavation
from the burrow, prey-capture and reproduction.         The aim of this study was to
determine the effect of prolonged aestivation on the activity levels of metabolic
enzymes (cytochrome c oxidase [CCO], lactate dehydrogenase [LDH] and citrate
synthase [CS]) from selected skeletal muscles (cruralis, gastrocnemius, sartorius,
iliofibularis and rectus abdominus) and the liver of C. alboguttata. Furthermore, we
wished to determine whether the coordinated down-regulation in metabolic activity
varied with muscle or tissue type.          The activity level of CS was significantly
reduced after 6 and 9 months of aestivation in all tissues except for the cruralis and
the liver. LDH activity was significantly lower in the sartorius and rectus abdominus
muscles after prolonged aestivation, but remained at control levels in the remaining
tissues. The activity of CCO was significantly lower in the gastrocnemius and rectus
abdominus during aestivation, but was unchanged in the sartorius, the iliofibularis
and the liver. The results suggest that the energy pathways involved with the
production and consumption of ATP are remodelled during prolonged aestivation,
and that remodelling and subsequent down-regulation of enzyme activity levels
varies with tissue type.




                                         35
    Citrate synthase activity does not account for age-related differences in
    maximum aerobic performance in House Sparrows (Passer domesticus).

             William A. Butemer1, Claus Bech2, and Mark A. Chappell3
1
 School of Biological Sciences, University of Wollongong, Wollongong, NSW, 2522, 2
Department of Biology, Norwegian University of Science and Technology, NO-7491
Trondheim, Norway, and 3 Department of Biology, University of California, Riverside,
                          Riverside, California 92521, USA.

We measured basal (BMR) and peak metabolic rates (PMR) in juvenile and adult
House Sparrows. Juvenile birds had significantly higher BMR, but lower PMR than
adult birds, despite having statistically indistinguishable body masses. We then
evaluated the relation between PMR and masses of central and peripheral organs
and found that pectoral muscle mass best correlated with PMR in both groups,
accounting for about 35% of the variation in pooled PMR. Because citrate synthase
(CS) has major importance in affecting the first committed step in the tricarboxylic
acid cycle, we characterized CS activity levels in extracted muscles to see if this
better explained age-related differences in peak aerobic performance. Surprisingly,
juvenile sparrows had significantly higher CS activity levels than adults (197.8 vs.
179.0 µmol g-1 min-1, respectively). This higher enzyme activity in juveniles was
completely offset by their significantly smaller proportion of flight musculature relative
to body mass (17.7 % in adults vs. 15.3% in juveniles). Consequently, ontogenetic
changes in relative sizes of organs best accounts for age-related differences in peak
metabolic rate.




                                           36
 Cooler temperatures increase sensitivity to ultraviolet B radiation in embryos
                and larvae of the frog Limnodynastes peronii

          Vincent O. van Uitregt1, Robbie S. Wilson1 and Craig E. Franklin1
1
    School of Integrative Biology, The University of Queensland, Brisbane, QLD 4072,
                                        Australia

Recent studies suggest that complex interacting processes are driving global
amphibian declines.      Increased ultraviolet B radiation in the solar spectrum
associated with ozone depletion has been implicated in declines, and evidence
suggests that the effects of UVb radiation on amphibians may be greater at cooler
temperatures. We tested the thermal sensitivity of UVb effects on amphibians in a
controlled factorial experiment using the striped marsh frog, Limnodynastes peronii
as a model species. We compared survival, growth and locomotor performance of
embryonic and larval L. peronii reared under low and high UVb exposures at both 20
and 30ºC. Embryonic and larval L. peronii proved extremely sensitive to UVb
damage and exhibited greater sensitivity at 20ºC compared to 30ºC. Embryonic
survival to Gosner stage 25 was unaffected by UVb exposure at 30ºC, but at 20ºC
survival was reduced to 52% under high UVb. Larval survival exhibited a similar
trend. At 20ºC, all tadpoles survived under low UVb, whereas under high UVb there
was 100% mortality after 15 days of exposure. At 30ºC, 86% survived under low
UVb, but only 46% survived under high UVb. Sublethal effects such as, embryonic
malformation, retarded larval growth and reduced larval swimming performance were
also greater at 20ºC compared to 30ºC. Our results strongly indicate that UVb
damage in amphibians is markedly increased at cooler temperatures. Thus,
populations of UVb sensitive species occurring at cold climates may be at greater risk
of declines due to increased solar UVb radiation.




                                          37
   Allosteric modulation of haemoglobin function in response to changes in
         oxygen supply and demand: insights from aquatic ectotherms

                                Rufus M.G. Wells

   School of Biological Sciences, The University of Auckland, Private Bag 92019,
                              Auckland, New Zealand

Phosphate compounds in the red blood cells of vertebrates play an important role in
modulating haemoglobin function whereby tissue oxygenation is maintained despite
changes in both environmental oxygen supply and metabolic demand. Three
examples from Gordon Grigg’s work on aquatic ectotherms illustrate how our thinking
has developed in terms of adaptive responses to seasonal temperature changes,
environmental hypoxia, and ontogeny.




                                        38
39
                          Tracking Crocodiles in the Field

                            Craig Franklin1 & Mark Read2
            1
             School of Integrative Biology, The University of Queensland,
                            Brisbane, QLD 4072, Australia
                      2
                       Queensland Parks and Wildlife Service,
                     PO Box 2066 Cairns QLD 4870, Australia


Determining the movement patterns of any species is difficult, but if the range of that
species is extensive, the species is cryptic, lives in remote locations or its behaviour
is modified by the continued presence of humans, then monitoring becomes
increasingly difficult. Biotelemetry provides a means by which to study animals
remotely in their natural habitats and provides a means to uncover the secret life of
crocs. Radio, satellite and acoustic telemetry and archival tags (data loggers) have
been deployed on crocodiles over the past few decades revealing exciting and new
information on how crocodiles move and function in their natural habitats.




                                           40
Author Index

                       Page

Alton, Lesley           27
Augee, Mike             6
Beeton, Bob             14
Bennett, Mike           13
Booth, David            12
Brice, Peter            8
Buttemer, Bill          36
Carrick, Frank          11
Courtice, Gillian       30
Coventry, Jocelyn       15
Ellis, Bill             10
Franklin, Craig         42
Geiser, Fritz           9
Grigg, Gordon           20
Hero, Jean-Marc         22
Holmgren, Susanne       32
Hulbert, Tony           33
Jacklyn, Peter          21
Jessop, Tim             7
Joss, Jean              16
Kirshner,David          31
Langridge, Melissa      34
Lunney, Dan             17
McAlpine, Clive         23
McCallum, Hamish        19
Nilsson, Stefan         25
Pratt, Kirstin          28
Seymour, Roger          26
Shine, Rick             24
Sperling, Jannie        29
Symonds, Beth           35
van Uitregt, Vincent    37
Wells, Rufus            38




                              41

				
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