Indigenous peoples of western Arnhem Land, central northern Australia, have detailed knowledge of the rock kangaroos of the region, species that are little known to science. Information about the ecology of the species is required for their conservation and management. Ethnoecological studies can assist senior indigenous people with transfer of knowledge and can give respect and meaningful employment to those involved. We used semidirected interviews in the regional vernacular, Bininj Kunwok, to record indigenous knowledge of the ecology of the four rock kangaroo species (Petrogale brachyotis, P. concinna, Macropus bernardus and M. robustus). Discussions focussed on habitat preferences, diet, activity patterns, reproduction, predation, and hunting practices. The ethnoecological knowledge of the rock kangaroo species was extensive, and both complemented and extended that reported in the scientific literature. In contrast to scientific understanding of taxonomy and ecology, consultants recognized the rock kangaroos as a natural group. They also described subtle differences in the species’ comparative ecology. The methodology used proved highly successful and we recommend recording indigenous knowledge of the ecology of fauna species in the local vernacular wherever possible. This study is one of the most comprehensive ethnozoological studies of a group of species undertaken in Australia.
Elephants (Loxodonta africana) exhibit pronounced sexual dimorphism, and in this study we test the prediction that the differences in body size and sociality are significant enough to drive divergent foraging strategies and ultimately sexual segregation. Body size influences the foraging behaviour of herbivores through the differential scaling coefficients of metabolism and gut size, with larger bodied individuals being able to tolerate greater quantities of low-quality, fibrous vegetation, whilst having lower mass-specific energy requirements. We test two distinct theories: the scramble competition hypothesis (SCH) and the forage selection hypothesis (FSH). Comprehensive behavioural data were collected from the Pongola Game Reserve and the Phinda Private Game Reserve in South Africa over a 2.5-year period. The data were analysed using sex as the independent variable. Adult females targeted a wider range of species, adopted a more selective foraging approach and exhibited greater bite rates as predicted by the body size hypothesis and the increased demands of reproductive investment (lactation and pregnancy). Males had longer feeding bouts, displayed significantly more destructive behaviour (31% of observations, 11% for females) and ingested greater quantities of forage during each feeding bout. The independent ranging behaviour of adult males enables them to have longer foraging bouts as they experience fewer social constraints than females. The SCH was rejected as a cause of sexual segregation due to the relative abundance of low quality forage, and the fact that feeding heights were similar for both males and females. However, we conclude that the differences in the foraging strategies of the sexes are sufficient to cause spatial segregation as postulated by the FSH. Sexual dimorphism and the associated behavioural differences have important implications for the management and conservation of elephant and other dimorphic species, with the sexes effectively acting as distinct “ecological species”. 相似文献
Object exploration is an increasingly popular experimental paradigm in behavioral sciences. We have begun a series of studies with mice specifically looking at the parameters that influence behaviors in this test. The aim of the present study was to examine the effect of object type on performance in the object exploration test. More specifically, adult male C57BL/6J mice were trained and tested using objects that could be climbed (CLIMB) or with those that could only be touched (TOUCH). The results show that activity is affected by the presentation of objects, with object type interacting with some of these changes. C57 mice explored objects that can be climbed over significantly longer than objects that can only be touched and a more rapid habituation was observed using objects that could only be touched. Robust recognition memory was observed in both groups of mice, however mice in the CLIMB group exhibited a significantly greater discrimination index compared to mice in the TOUCH group. Taken together, these findings demonstrate that the selection of objects is of critical importance and it is recommended that special attention be given to the functional (affordant) properties of the objects to-be-used in future studies. 相似文献
Polyphenism, which allows a single genotype to express multiple discrete phenotypes in response to environmental cues, is
an adaptive trait in heterogeneous environments. Pond hydroperiod is an important ecological parameter affecting amphibian
life history, and variation in local pond hydrology has been hypothesized to play a role in species divergence via changes
in polyphenism. The eastern newt (Notophthalmus viridescens) expresses life cycle polyphenism. Larvae develop along three possible pathways: metamorphosis to aquatic lunged adult via
a terrestrial juvenile (eft) stage, metamorphosis directly to an aquatic lunged adult, or maturation directly to an aquatic
gilled adult without metamorphosis (i.e., paedomorphosis). Subspecies of N. viridescens vary in their polyphenic patterns, suggesting possible adaptation to different environments. However, no studies have experimentally
tested how genetic and environmental components contribute to the observed differences among subspecies and whether such differences
may facilitate divergence. We tested whether adaptation to local pond hydrology via polyphenic changes existed among subspecies
by rearing larvae of three subspecies (N. v. dorsalis, N. v. louisianensis, and N. v. viridescens) along three hydroperiod regimes (short, long, and constant) in outdoor artificial ponds. We found that larval N. v. viridescens obligately metamorphosed to efts under all hydroperiods, whereas N. v. dorsalis and N. v. louisianensis exhibited plasticity: larvae metamorphosed to efts under drying conditions but metamorphosed directly to aquatic adults or
became paedomorphic in constant water. Also, N. v. viridescens metamorphosed to efts faster and at a smaller body size than the other two subspecies. These data suggest that subspecies
of N. viridescens are adapted to different pond hydroperiods, supporting the potential for polyphenism to facilitate divergence. Canalizing
selection for certain alternative phenotypes within a single species in which other populations remain plastic may play an
important role in the initiation of ecological divergence. 相似文献
The value of scientific studies increases and is extended when their data are stored in a manageable and accessible format. This is demonstrated through development of a raccoon ecology database (REDB) to store, manage and disseminate available peer-reviewed and unpublished data on raccoon (Procyon lotor) biology, ecology and raccoon rabies, including citations for data sources. Over 800 documents were identified and citations for them entered into the database as literature references. Approximately 1000 trait values were entered from almost 200 of these sources. These data included estimates of population density, survival rates, rabies incubation period, litter size, body weight, dispersal distance and home-range size, often by age or sex class. Each datum is linked to a citation for its source, and to information about location and land use in the study area, time of year the study was undertaken, sample size, and variance. The relational database design enables querying and easy updating and manipulation of data.
The relational data model is presented, as is its application in further developing an individual-based, spatially-explicit population model of raccoon rabies. Using information queried from the REDB benefits model development by: i) assessing the appropriateness of input parameter values, ii) providing sources for citing input values, iii) parameterising the model to different geographic regions, iv) enabling meta-analyses for evaluating model structure, as well as further contributing to parameterisation at specific locations, and v) providing biologically appropriate parameter input values for model sensitivity testing. The REDB is a useful research resource that will increase in value with ongoing inclusion of data from future raccoon and raccoon rabies studies and serves as a model for database design and research applications to other species. The database and an empty database for use with other species are available online (http://redb.nrdpfc.ca). 相似文献
When pasture land is abandoned, there are, in many cases, inhibitory factors that slow the rate of transition to a natural
vegetation. Accordingly, the planned management of restoration has become an important issue in various parts of the world,
where environmental conditions can vary widely. Although tree plantations are widely used as a management tool for restoration,
there have been few studies addressing the practical aspects of the procedure. I examined effects of tree plantations within
the framework of an evaluation of methods for restoring abandoned pasture on Hokkaido, northern Japan. I developed and analyzed
vegetation maps spanning the past 57 years for the old-growth site influenced by artificial disturbance; the procedure revealed
the pattern of change in the vegetation cover. Matrix model analysis showed that intensive use of plantations contributed
to reduction of the area occupied by dwarf bamboo and pasture land (i.e., superior to simple abandonment). Furthermore, the
field study of vegetation types and changes in species composition over 20 years suggests that plantations have contributed
to a reduction in the effects of factors that inhibit revegetation. However, the establishment of monoculture plantations
is frequently viewed skeptically as a procedure that is applied without fundamental ecological knowledge. For sustained management,
adequate historical and ecological information on the restoration site should be provided to all stakeholders.
An erratum to this article can be found at 相似文献