Singlespecies metapopulation dynamics
... reassuring consideration for conservation biologists, one should remember that dispersal rates are likely to change so slowly that metapopulations living in ...
... reassuring consideration for conservation biologists, one should remember that dispersal rates are likely to change so slowly that metapopulations living in ...
Predictors of species sensitivity to fragmentation
... directly. This is due to the fact that in the case of fragmentation driven by land use change and associated habitat clearing, we generally lack any information on population size prior to fragmentation. Likewise, fragmentation experiments usually have not collated information on population size bef ...
... directly. This is due to the fact that in the case of fragmentation driven by land use change and associated habitat clearing, we generally lack any information on population size prior to fragmentation. Likewise, fragmentation experiments usually have not collated information on population size bef ...
The Phanerozoic Eon - Jutzi
... • Within a few million years, organisms began to develop mobility and the first modern animals were born ...
... • Within a few million years, organisms began to develop mobility and the first modern animals were born ...
Genetic diversity
... Earth has experienced five mass extinctions • In the past 440 million years, mass extinctions have eliminated at least 50% of all species • After every mass extinction the biodiversity returned to or exceeded its original state ...
... Earth has experienced five mass extinctions • In the past 440 million years, mass extinctions have eliminated at least 50% of all species • After every mass extinction the biodiversity returned to or exceeded its original state ...
Biodiversity - Pcpolytechnic
... Benefits of Biodiversity • Ecosystem functions • Ecosystem services • Cleaning water, • Cleaning air, • Habitat & breeding areas for wildlife, … ...
... Benefits of Biodiversity • Ecosystem functions • Ecosystem services • Cleaning water, • Cleaning air, • Habitat & breeding areas for wildlife, … ...
Chapter 6
... shun) events. Extinction occurs when the last individual organism of a species dies. A mass extinction occurs when many species become extinct within a few million years or less. The fossil record contains evidence that five mass extinction events have occurred during the Phanerozoic eon, as shown i ...
... shun) events. Extinction occurs when the last individual organism of a species dies. A mass extinction occurs when many species become extinct within a few million years or less. The fossil record contains evidence that five mass extinction events have occurred during the Phanerozoic eon, as shown i ...
On the Use of Surrogate Species in Conservation Biology
... Indicators of population trends in other organisms are usually a single species and may be most successful if the principal factors affecting their population size are well understood (Landres 1983). They need to be monitored relatively easily at least during one stage of their life cycle (Temple & ...
... Indicators of population trends in other organisms are usually a single species and may be most successful if the principal factors affecting their population size are well understood (Landres 1983). They need to be monitored relatively easily at least during one stage of their life cycle (Temple & ...
Evolution, biodiversity, and Population Ecology
... Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings ...
... Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings ...
Population
... Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings ...
... Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Copyright © 2008 Pearson Education, Inc., publishing as Benjamin Cummings ...
Ecological benefits of the temporary nature concept
... Destruction can have a more far-reaching negative impact on species that choose temporary nature for reproduction. Destruction should not be done during the breeding season, or breeding should be actively avoided before destruction. ...
... Destruction can have a more far-reaching negative impact on species that choose temporary nature for reproduction. Destruction should not be done during the breeding season, or breeding should be actively avoided before destruction. ...
Geographic range of West African freshwater fishes
... considered as a geographic range size index. This measurement is therefore not the same as the surface area of geographic range, but has two advantages in the present case. Firstly it is better-suired to the presencelabsence per river data used here from which i t is difficult-if not impossible- to ...
... considered as a geographic range size index. This measurement is therefore not the same as the surface area of geographic range, but has two advantages in the present case. Firstly it is better-suired to the presencelabsence per river data used here from which i t is difficult-if not impossible- to ...
Biodiversity in grasslands: current changes and scenarios for the
... l extraction of resources (e.g. mineral nutrients); l changes in energy and material transfers (e.g. individual plant growth and nutrient mineralization); l changes in species composition (e.g. addition of crops and weeds) and substances (i.e. agrochemicals, principally pesticides and fertilizers); ...
... l extraction of resources (e.g. mineral nutrients); l changes in energy and material transfers (e.g. individual plant growth and nutrient mineralization); l changes in species composition (e.g. addition of crops and weeds) and substances (i.e. agrochemicals, principally pesticides and fertilizers); ...
Species abundance distributions and diversity profiles
... in the community (Murray et al., 1999), and a larger set of species with intermediate abundance and usually some more common species. Occasionally, there are a few very dominant species that might be considered as indicators, e.g. for mass occurrences of invasive plants, blooms of therophytes or bus ...
... in the community (Murray et al., 1999), and a larger set of species with intermediate abundance and usually some more common species. Occasionally, there are a few very dominant species that might be considered as indicators, e.g. for mass occurrences of invasive plants, blooms of therophytes or bus ...
Drawing ecological inferences from coincident patterns of
... disciplines for essentially their entire histories as named fields of study, they have often travelled somewhat independent pathways of conceptual advancement (Holt 2005; Vellend 2010). The last 15 years or so has seen a major resurgence of interest in explicit integration of ecological and evolutio ...
... disciplines for essentially their entire histories as named fields of study, they have often travelled somewhat independent pathways of conceptual advancement (Holt 2005; Vellend 2010). The last 15 years or so has seen a major resurgence of interest in explicit integration of ecological and evolutio ...
Enquiry 4 Almost Armageddon!
... The bulk of the enquiry focuses on one period of geologic time, the Permian, and challenges pupils to solve one of the greatest mysteries of deep time; an event that nearly exterminated all life on Earth. The end of the Permian period 252 million years ago was marked by a catastrophic event of some ...
... The bulk of the enquiry focuses on one period of geologic time, the Permian, and challenges pupils to solve one of the greatest mysteries of deep time; an event that nearly exterminated all life on Earth. The end of the Permian period 252 million years ago was marked by a catastrophic event of some ...
FREE Sample Here
... 20) In a hypothetical environment, fishes called pike-cichlids are visual predators of algae-eating fish (in other words, they locate their prey by sight). If a population of algae-eaters experiences predation pressure from pike-cichlids, which of the following is least likely to be observed in the ...
... 20) In a hypothetical environment, fishes called pike-cichlids are visual predators of algae-eating fish (in other words, they locate their prey by sight). If a population of algae-eaters experiences predation pressure from pike-cichlids, which of the following is least likely to be observed in the ...
Ecological communities in variable environments : dynamics
... negative densities) and thus such systems are termed unfeasible. In an unfeasible community, if all species are initiated with positive densities, some species show exponential decline in the absence of any perturbations. This term comes from economics, indicating that if a community is diversified ...
... negative densities) and thus such systems are termed unfeasible. In an unfeasible community, if all species are initiated with positive densities, some species show exponential decline in the absence of any perturbations. This term comes from economics, indicating that if a community is diversified ...
Coevolution between native and invasive plant competitors
... Coevolution between competitors Coevolutionary relationships between competitors are not as well-studied as coevolution among species of different trophic levels (such as plant/herbivore interactions or pathogen/host relationships), and most studies of coevolution between competitors have been condu ...
... Coevolution between competitors Coevolutionary relationships between competitors are not as well-studied as coevolution among species of different trophic levels (such as plant/herbivore interactions or pathogen/host relationships), and most studies of coevolution between competitors have been condu ...
122. Woodruff, D.S. and G.A.E. Gall. Genetics and conservation. In
... linked to human welfare. Biological diversity refers to the variety and variability among living organisms and the ecosystems in which they interact. Such diversity has evolved over a billion years and is responsible for ecological processes which sustain all life, including that of our own recently ...
... linked to human welfare. Biological diversity refers to the variety and variability among living organisms and the ecosystems in which they interact. Such diversity has evolved over a billion years and is responsible for ecological processes which sustain all life, including that of our own recently ...
Biodiversity: an introduction - European Capitals of Biodiversity
... abundance are known as keystone species. The niches and interactions of such species affect their ecosystem as a whole. Changes in the abundance and distribution of keystone species can thus have profound effects on the status of other species and indeed the pertaining ecosystem. ...
... abundance are known as keystone species. The niches and interactions of such species affect their ecosystem as a whole. Changes in the abundance and distribution of keystone species can thus have profound effects on the status of other species and indeed the pertaining ecosystem. ...
8 Habitat matrix effects on the structure and dynamic
... spatially discrete habitats and are populated by many taxa with complex life cycles, including terrestrial adults that may move among ponds, as insects and amphibians do. The metacommunity perspective differs from metapopulation perspectives, in that the principal issue in metapopulation theory is t ...
... spatially discrete habitats and are populated by many taxa with complex life cycles, including terrestrial adults that may move among ponds, as insects and amphibians do. The metacommunity perspective differs from metapopulation perspectives, in that the principal issue in metapopulation theory is t ...
The controversy space on Quaternary megafaunal extinctions
... Controversy spaces are dynamic structures. The foci of discussion may change over time, a process called refocalization. This refocalization can occur for several reasons: a new actor may appear with a new hypothesis, a focus may become part of the common ground (as a result of agreements reached du ...
... Controversy spaces are dynamic structures. The foci of discussion may change over time, a process called refocalization. This refocalization can occur for several reasons: a new actor may appear with a new hypothesis, a focus may become part of the common ground (as a result of agreements reached du ...
The influence of biodiversity on invasibility of terrestrial plant
... remaining species to dominate the plot. These plots are then subjected to propagules of invasive species and after a certain amount of time the biomasses of native species and invaders are compared within and between plots. These experiments generally demonstrate that there is an effect of diversity ...
... remaining species to dominate the plot. These plots are then subjected to propagules of invasive species and after a certain amount of time the biomasses of native species and invaders are compared within and between plots. These experiments generally demonstrate that there is an effect of diversity ...
The Endangered Species Act of 1973
... of environmental excellence. The compromising language of this provision requires merely that environmental protection be one of a totality of concerns to be taken into consideration. Thus, before an environmental safeguard is required, it (1) must be "practicable", and (2) must .outweigh other nati ...
... of environmental excellence. The compromising language of this provision requires merely that environmental protection be one of a totality of concerns to be taken into consideration. Thus, before an environmental safeguard is required, it (1) must be "practicable", and (2) must .outweigh other nati ...
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms (taxon), normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point. Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa, where a species presumed extinct abruptly ""reappears"" (typically in the fossil record) after a period of apparent absence.The age of the Earth is about 4.54 billion years old. The earliest undisputed evidence of life on Earth dates at least from 3.5 billion years ago, during the Eoarchean Era after a geological crust started to solidify following the earlier molten Hadean Eon. There are microbial mat fossils found in 3.48 billion-year-old sandstone discovered in Western Australia. Other early physical evidence of a biogenic substance is graphite in 3.7 billion-year-old metasedimentary rocks discovered in Western Greenland. More than 99 percent of all species, amounting to over five billion species, that ever lived on Earth are estimated to be extinct. Estimates on the number of Earth's current species range from 10 million to 14 million, of which about 1.2 million have been documented and over 86 percent have not yet been described.Through evolution, species arise through the process of speciation—where new varieties of organisms arise and thrive when they are able to find and exploit an ecological niche—and species become extinct when they are no longer able to survive in changing conditions or against superior competition. The relationship between animals and their ecological niches has been firmly established. A typical species becomes extinct within 10 million years of its first appearance, although some species, called living fossils, survive with virtually no morphological change for hundreds of millions of years. Mass extinctions are relatively rare events; however, isolated extinctions are quite common. Only recently have extinctions been recorded and scientists have become alarmed at the current high rate of extinctions. Most species that become extinct are never scientifically documented. Some scientists estimate that up to half of presently existing plant and animal species may become extinct by 2100.