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Seed dispersal strategies and the threat of defaunation in a Congo
Seed dispersal strategies and the threat of defaunation in a Congo

... Recent studies indicate that seed dispersal plays a prominent role in recruitment limitation, gene flow, metapopulation dynamics, colonisation potential and plant migration in response to past and future climate change, maintenance of biodiversity, and more (Schupp et al. 2010). As predicted by mode ...
Rossberg, A. G. (2012). Food webs. In A. Hastings
Rossberg, A. G. (2012). Food webs. In A. Hastings

... The scheme is perhaps more realistic than this interpretation. The actual speciations can have occurred allopatrically or at distant locations or times. In the focal community, such processes would simply be reflected by invasions of species that are more or less similar to existing ones. Examples o ...
Tilman et al. Science 2001
Tilman et al. Science 2001

... biomass on species number and composition was not explained solely by sampling effects for a species pool containing some poorly performing species. We tested the sampling hypothesis that the most productive species determined the effects of diversity (6, 9, 17) by retaining in analyses of year 2000 ...
Ecological community integration increases with added trophic
Ecological community integration increases with added trophic

... and economics (Standish, 2000). This wide-ranging homology suggests that the Lotka-Volterra equations are a canonical model for the study of complex systems. In terms of generality, the state variables ‘species’ might be replaced with ‘agents’ (e.g., genes, individuals, business firms, or nation-sta ...
53_Lectures_PPT
53_Lectures_PPT

... • The total of a species’ use of biotic and abiotic resources is called the species’ ecological niche • Ecologically similar species can coexist in a community if there are one or more significant differences in their niches • As a result of competition, a species’ fundamental niche may differ from ...
as a PDF
as a PDF

... 2.2. Analysis of morphospace Thirteen external morphological traits (Appendix C) were taken with dial calipers (precision: 0.1 mm) in a standardized manner on specimens obtained from museums. We chose measurements that reflect various facets of anuran trophic ecology, habitat use, and modes of locomo ...
Invasiveness in plant communities with feedbacks
Invasiveness in plant communities with feedbacks

... determining invasiveness, theoretical models are needed for exploring the complex nature of the interaction of these ecological influences (Hastings et al. 2005). Recently, Levine et al. (2006) developed a one-dimensional, discrete-in-time, single-species integrodifference model to examine the likel ...
Ecological and evolutionary insights from species invasions
Ecological and evolutionary insights from species invasions

... ecology and conservation biology, they are also useful for addressing a range of basic research questions in ecology, evolutionary biology and biogeography. The reasons for this are fourfold. First, species invasions provide unplanned experiments across large spatial and temporal scales, ones that a ...
Prioritizing Ecosystems, Species, and Sites for Restoration
Prioritizing Ecosystems, Species, and Sites for Restoration

... Little work has been done to quantify the relative functional importance of particular ecosystem types within the broader mosaic of ecosystems that constitute the regional landscape. Using extent of decline in area or quality as a primary criterion for prioritizing ecosystems for restoration carries ...
Conservation of species interaction networks
Conservation of species interaction networks

... with can still be pollinated/dispersed by other more generalist species (Memmott et al., 2004; Bascompte et al., 2006; Fortuna and Bascompte, 2006; Okuyama and Holland, 2008). Thus, a nested interaction structure provides a buffer against secondary extinctions or temporal fluctuations in the abundanc ...
biolcons_biodiv_loss - digital
biolcons_biodiv_loss - digital

... 2009), which has been recently updated by the threats classification scheme version 3.0 (http://www.iucnredlist.org/static/major_threats). The listing of the 10 driver categories in each bird species fact sheet was translated to a presence–absence matrix in which bird species were rows and extinction ...
Regeneration ecology, conservation status and recovery planning
Regeneration ecology, conservation status and recovery planning

... Zealand, Lord Howe Island, and Papua New Guinea. All the New Zealand species are endemic. Allan (1961) recognises 32 species and Druce (1992) 35 in New Zealand. O. hectorii was first described by Hooker (1864), with the type from the ‘Lakes District’, probably the Matukituki valley, Lake Wanaka. Two ...
Effects of Competition, Predation, and Dispersal on Species
Effects of Competition, Predation, and Dispersal on Species

... alone) and eP (when it coexists with the predator). An inferior competitor, species 2 is excluded from patches occupied by species 1 except in the presence of the predator. Species 2 goes extinct at a rate (e) that is unaffected by the presence of the predator. Occupied patches can potentially be in ...
Species diversity and dominance-richness relationships for ground
Species diversity and dominance-richness relationships for ground

... is typically unimodal (humped), due to the combined effects of environmental stress, abundance-frequency distributions and interspecific competition (PARR & al. 2005). In extreme environments or periods of unfavourable abiotic conditions, stress leads to low numbers of both dominant ants and total s ...
PDF Full-text
PDF Full-text

... i.e., following the principle of parsimony, we introduce the minimal and sufficient complexity to achieve the desired goal. Furthermore, higher dimensional niches do not introduce dramatic changes (see, for example, [37]). We choose integer niche variables rather than real variables, because we do n ...
An Analysis of Abundance and Catch Probability of Sharks off Coastal Louisiana
An Analysis of Abundance and Catch Probability of Sharks off Coastal Louisiana

... Generally the study sites consisted of one offshore station and two inshore stations. The offshore station was near East Timbalier Island (station 1). The others were east and west of Casse Tette Island, labeled stations 2 and 3 respectively. Figure 1 shows the geographical locations of the three si ...
pdf - New Zealand Ecological Society
pdf - New Zealand Ecological Society

... Abstract: Squamata are one of the most threatened groups among island vertebrates, facing high pressure from exotic species. However, the contribution of small terrestrial reptiles in invasive rodents’ diet remains poorly investigated, partly because of the lack of tools for accurately identifying c ...
Differences in diet between two rodent species, Mastomys
Differences in diet between two rodent species, Mastomys

... Gerbilliscus vicinus, coexisting in fallow land in central Tanzania were studied to assess the degree of diet differentiation among them. Dietary niche breadth of G. vicinus was greater than that of M. natalensis in all stages of the maize cropping seasons. The rodent species studied overlapped cons ...
Invasive species
Invasive species

... Do certain environments increase the vulnerability of animal species to extinctions? As the reader may have noticed, most of the examples of extinctions and extirpations caused by invasive species that have been presented involve the introduction of new species to islands or freshwater systems. With ...
Invasive Species in the Sonoran Desert
Invasive Species in the Sonoran Desert

... the ecosystem. Cats are an example of this. Although feral cats constitute a major  problem in urban and suburban areas, they don’t do as well beyond urban areas  because of predation by coyotes and bobcats. (Crooks & Soule, 1999)Other species  have found some balance with the ecosystem. Honeybees,  ...
Species-species association strengths
Species-species association strengths

... randomly on various habitats by chance. A positive association indicated that a species was found more often than expected by chance, while a negative value indicated that a species was found less often then by chance. Species habitat associations were determined by combining UPC substrate and relie ...
Edge effects of long-term glades on the invertebrate abundance and
Edge effects of long-term glades on the invertebrate abundance and

... encroaching into savannahs areas in Kenya. T. camphoratus is a small evergreen shrub or tree of up to 9 meters and adapted to a wide variety of habitats throughout sub-Saharan Africa, especially in drier areas (Meg et al., 2002). It is a hardy plant that can regenerate quickly when cut or burnt (Noa ...
13.1 Ecologists Study Relationships
13.1 Ecologists Study Relationships

... (relationships) among living things, and between living things and their surroundings. – Studying how life interacts within the biosphere. • Scientists used to study each organism separately as if they existed in isolation. ...
A comparative growth analysis between alien invader and native
A comparative growth analysis between alien invader and native

... Differences in RGR between species were tested with an ANCOVA on the natural logarithm of total dry mass or leaf area, with number of days after transplanting into the culture system as covariate, and were considered significantly different when the interaction species ¥ time was significant. As onl ...
Ecology of Native and Exotic Anolis lizards in Southern Florida.
Ecology of Native and Exotic Anolis lizards in Southern Florida.

... resampling these locations through a greater period of time. We also recommend increasing the number of localities across which A. carolinensis population can be compared. A larger data set through several more years might enable a more conclusive statement regarding trends in the native anole’s pop ...
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Occupancy–abundance relationship

In ecology, the occupancy–abundance (O–A) relationship is the relationship between the abundance of species and the size of their ranges within a region. This relationship is perhaps one of the most well-documented relationships in macroecology, and applies both intra- and interspecifically (within and among species). In most cases, the O–A relationship is a positive relationship. Although an O–A relationship would be expected, given that a species colonizing a region must pass through the origin (zero abundance, zero occupancy) and could reach some theoretical maximum abundance and distribution (that is, occupancy and abundance can be expected to co-vary), the relationship described here is somewhat more substantial, in that observed changes in range are associated with greater-than-proportional changes in abundance. Although this relationship appears to be pervasive (e.g. Gaston 1996 and references therein), and has important implications for the conservation of endangered species, the mechanism(s) underlying it remain poorly understood
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