Adaptive Radiation - Princeton University Press
... species into an array of descendant species that differ in the way they exploit the environment. When the differentiation has proceeded rapidly, the evolutionary transitions from one state to another can readily be characterized and strongly interpreted. Angiosperm plants, dinosaurs, and marsupial m ...
... species into an array of descendant species that differ in the way they exploit the environment. When the differentiation has proceeded rapidly, the evolutionary transitions from one state to another can readily be characterized and strongly interpreted. Angiosperm plants, dinosaurs, and marsupial m ...
Evolutionary food web model based on body masses gives realistic
... Classical models addressing the structure and stability of food webs are based on stochastic algorithms that produce structural patterns similar to empirically measured food webs [1], such as the niche model [2] or the cascade model [3]. A more recent approach is to use the empirically found allomet ...
... Classical models addressing the structure and stability of food webs are based on stochastic algorithms that produce structural patterns similar to empirically measured food webs [1], such as the niche model [2] or the cascade model [3]. A more recent approach is to use the empirically found allomet ...
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 ...
Chapter 3 - Santa Rosa Home
... helps scientists organize and name them Categories reflect evolutionary relationships Scientists use physical and genetic characteristics to organize ...
... helps scientists organize and name them Categories reflect evolutionary relationships Scientists use physical and genetic characteristics to organize ...
Australian Wildlife Protection Council (Word
... thousands of years you are in danger of putting the species at risk. Precedents have been set in other parts of the world where large populations of a species have faced extinctions after widespread and destructive 'culling' programs. Many of these species suffer incursions of exotic bacterias and v ...
... thousands of years you are in danger of putting the species at risk. Precedents have been set in other parts of the world where large populations of a species have faced extinctions after widespread and destructive 'culling' programs. Many of these species suffer incursions of exotic bacterias and v ...
Ch11 Lecture 1.competition
... found that competition with Semibalanus excluded Chthamalus from all but the top of the intertidal zone. Semibalanus smothered, removed, or crushed the other species. However, Semibalanus dried out and survived poorly at the top of the ...
... found that competition with Semibalanus excluded Chthamalus from all but the top of the intertidal zone. Semibalanus smothered, removed, or crushed the other species. However, Semibalanus dried out and survived poorly at the top of the ...
Invasive Alien Species - European Commission
... gathered information from the three different European regions. They compiled a database of 52480 vegetation plots spread throughout contrasting climatic conditions and containing a wide range of flora. Catalonia, in north-eastern Spain is a region with predominantly Mediterranean-sub-Mediterranean ...
... gathered information from the three different European regions. They compiled a database of 52480 vegetation plots spread throughout contrasting climatic conditions and containing a wide range of flora. Catalonia, in north-eastern Spain is a region with predominantly Mediterranean-sub-Mediterranean ...
Trophically Unique Species Are Vulnerable to Cascading Extinction Linköping University Postprint
... Quince et al. 2005; Eklöf and Ebenman 2006). The trophic position of the primary extinction is also important but tends to interact with connectance. In sparsely connected communities, extinction of a top predator is less likely to cause secondary extinctions than extinction of a basal species (Bor ...
... Quince et al. 2005; Eklöf and Ebenman 2006). The trophic position of the primary extinction is also important but tends to interact with connectance. In sparsely connected communities, extinction of a top predator is less likely to cause secondary extinctions than extinction of a basal species (Bor ...
Taxonomic inflation: its influen ce on macroecology and conservation
... whereas local diversity changes only with new discoveries (Box 1). Species-area curves, turnover in community composition and plots of regional against global geographical range would become steeper following taxonomic inflation. These quantitative effects of inflation will depend on the relative ge ...
... whereas local diversity changes only with new discoveries (Box 1). Species-area curves, turnover in community composition and plots of regional against global geographical range would become steeper following taxonomic inflation. These quantitative effects of inflation will depend on the relative ge ...
Indicators for Monitoring Biodiversity: A
... The hierarchy concept suggests that biodiversity be monitored at multiple levels of organization, and at multiple spatial and temporal scales. No single level of organization (e.g., gene, population, community) is fundamental, and different levels of resolution are appropriate for different question ...
... The hierarchy concept suggests that biodiversity be monitored at multiple levels of organization, and at multiple spatial and temporal scales. No single level of organization (e.g., gene, population, community) is fundamental, and different levels of resolution are appropriate for different question ...
Impact of maximum sustainable yield on competitive community
... value decreases toward the MSY of one population. In the next example (Fig. 2) we investigate how TMSY affects populations characterized by a considerable difference in biotic potential (r1 ¼1, r2 ¼5). For a relatively small value of ab (ab ¼0.06) TMSY is obtained (Fig. 2a), both populations are pos ...
... value decreases toward the MSY of one population. In the next example (Fig. 2) we investigate how TMSY affects populations characterized by a considerable difference in biotic potential (r1 ¼1, r2 ¼5). For a relatively small value of ab (ab ¼0.06) TMSY is obtained (Fig. 2a), both populations are pos ...
butterfly habitat - North American Butterfly Association
... too small for the population to survive. It can take years for the consequences of habitat reduction to result in butterfly population extinction. But the likelihood of extinction is set in motion once that often unknown threshold of small habitat size gets crossed. Butterfly conservation experience ...
... too small for the population to survive. It can take years for the consequences of habitat reduction to result in butterfly population extinction. But the likelihood of extinction is set in motion once that often unknown threshold of small habitat size gets crossed. Butterfly conservation experience ...
megafauna extinction - Harvard Computer Society
... versus climate change debate, developing interesting new theories that ignore both. One of these is the hyperdisease hypothesis, which argues that humans brought a virulent disease to North America when they crossed the Bering Strait. This disease could have been dormant either in their own bodies o ...
... versus climate change debate, developing interesting new theories that ignore both. One of these is the hyperdisease hypothesis, which argues that humans brought a virulent disease to North America when they crossed the Bering Strait. This disease could have been dormant either in their own bodies o ...
endangered species
... Currently the lynx is a listed endangered species in most of the lower 48 states. And what about all of those species of plants that become extinct every year, especially those that we may have never even known existed? Each time we lose a species, its future benefits could be lost forever. EXTINCTI ...
... Currently the lynx is a listed endangered species in most of the lower 48 states. And what about all of those species of plants that become extinct every year, especially those that we may have never even known existed? Each time we lose a species, its future benefits could be lost forever. EXTINCTI ...
Rewilding and Biodiversity
... back into the Pleistocene when huge mammals dominated the continent’s ecosystems. Starting between 11,000 and 12,000 years ago, the megafauna virtually disappeared. The die-off was brief, lasting only about 2,000 years. Human beings are implicated in this catastrophic extirpation—sometimes referred ...
... back into the Pleistocene when huge mammals dominated the continent’s ecosystems. Starting between 11,000 and 12,000 years ago, the megafauna virtually disappeared. The die-off was brief, lasting only about 2,000 years. Human beings are implicated in this catastrophic extirpation—sometimes referred ...
Extinction thresholds: insights from simple models
... Extinction has played a major role in the organization of life on Earth. Almost all species which have existed at some point have already gone extinct. This unavoidable outcome, however, has been aggravated in the last few centuries due to human activity. Since 1600, the extinction of more than 485 ...
... Extinction has played a major role in the organization of life on Earth. Almost all species which have existed at some point have already gone extinct. This unavoidable outcome, however, has been aggravated in the last few centuries due to human activity. Since 1600, the extinction of more than 485 ...
untitled - digital-csic Digital CSIC
... species underscores that the same fragmentation process can have very different, and complex, consequences for the population genetic structure of plants. This idiosyncrasy renders generalizations across natural systems very difficult and highlights the need of context-oriented guidelines for an eff ...
... species underscores that the same fragmentation process can have very different, and complex, consequences for the population genetic structure of plants. This idiosyncrasy renders generalizations across natural systems very difficult and highlights the need of context-oriented guidelines for an eff ...
Initial scoping for the thematic assessment of invasive alien species
... assess the global diversity of invasive alien species that affect biodiversity and ecosystems services; the extent of the threat posed by such species to various categories of biodiversity and ecosystems services, including impacts on agrobiodiversity and food, health and livelihood security; the ma ...
... assess the global diversity of invasive alien species that affect biodiversity and ecosystems services; the extent of the threat posed by such species to various categories of biodiversity and ecosystems services, including impacts on agrobiodiversity and food, health and livelihood security; the ma ...
Species loss and secondary extinctions in simple and complex
... To investigate the response of communities to species loss we generate 1000 permanent replicate communities for each value of connectance in each food web configuration. From each of these permanent replicate communities we delete one species at a time and this is repeated for each species in the co ...
... To investigate the response of communities to species loss we generate 1000 permanent replicate communities for each value of connectance in each food web configuration. From each of these permanent replicate communities we delete one species at a time and this is repeated for each species in the co ...
- Island Biodiversity
... was barely in three figures, and the island had plenty of impenetrable forest and many wetlands/swamps, so overhunting is unlikely to have been a major factor for birds, though in Réunion the limited wetlands and larger human population would have made hunting a more important factor for waterbirds. ...
... was barely in three figures, and the island had plenty of impenetrable forest and many wetlands/swamps, so overhunting is unlikely to have been a major factor for birds, though in Réunion the limited wetlands and larger human population would have made hunting a more important factor for waterbirds. ...
150. Woodruff, D.S. Biodiversity: conservation and genetics. In
... that genetic variability (especially additive genetic variation) is a prerequisite for adaptation by evolution. Without the variability to work on natural selection can do little to improve a population's chances of surviving significant environmental change. It follows that small, isolated populati ...
... that genetic variability (especially additive genetic variation) is a prerequisite for adaptation by evolution. Without the variability to work on natural selection can do little to improve a population's chances of surviving significant environmental change. It follows that small, isolated populati ...
Emerging Issues Regarding Non-Native Species for Aquaculture
... attractive to mates, have lower quality eggs or sperm, or have other disadvantages. Others argue that most genetic variation is neutral and does not affect fitness. Still others are less concerned about genetic exchange if there are no noticeable negative effects, as with many sport fish stocking pr ...
... attractive to mates, have lower quality eggs or sperm, or have other disadvantages. Others argue that most genetic variation is neutral and does not affect fitness. Still others are less concerned about genetic exchange if there are no noticeable negative effects, as with many sport fish stocking pr ...
Action Plan for the Brush-tailed Rock-wallaby
... average of 1.2 young per year over their reproductive period, around 2-10 years of age (Taggart et al. 1997). Hazlitt et al. (2004) found that the species forms female based family groups that are closely related and usually number between 4-10 animals. They form close, polygynous bonds with a singl ...
... average of 1.2 young per year over their reproductive period, around 2-10 years of age (Taggart et al. 1997). Hazlitt et al. (2004) found that the species forms female based family groups that are closely related and usually number between 4-10 animals. They form close, polygynous bonds with a singl ...
PPT Slide - Tennessee State University
... In such a situation, each species should be able to maintain itself over only a narrow range of habitats – those to which it is best adapted – and beta diversity should be high. ...
... In such a situation, each species should be able to maintain itself over only a narrow range of habitats – those to which it is best adapted – and beta diversity should be high. ...
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.