Species functional redundancy, random extinctions and the stability
... We therefore looked in the literature for empirical studies that classify all species from a community into functional groups based on their effect on the functioning of the ecosystem. Surprisingly, we were unable to find any empirical study that conformed strictly to such a definition, however, Día ...
... We therefore looked in the literature for empirical studies that classify all species from a community into functional groups based on their effect on the functioning of the ecosystem. Surprisingly, we were unable to find any empirical study that conformed strictly to such a definition, however, Día ...
Ch 56 Notes - Dublin City Schools
... Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings ...
... Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings ...
Late Quaternary Extinctions: State of the Debate
... and short-faced bears disappeared at 35.4 and 24.8 kyr BP, respectively. A coalescence analysis of DNA sequences suggests that bison populations began to decline in size in Beringia at roughly this time (e.g., 35–40 kyr BP) and attributed bison demise to climate change rather than human impacts (Sha ...
... and short-faced bears disappeared at 35.4 and 24.8 kyr BP, respectively. A coalescence analysis of DNA sequences suggests that bison populations began to decline in size in Beringia at roughly this time (e.g., 35–40 kyr BP) and attributed bison demise to climate change rather than human impacts (Sha ...
The paradox of enrichment in phytoplankton by induced competitive
... two species competing for the same resources cannot coexist if all ecological factors remained constant20,26,27. This proposition is supported by several experimental studies using chemostat16,28,29. Many mathematical studies also demonstrate that the coexistence of many species is extremely unlikel ...
... two species competing for the same resources cannot coexist if all ecological factors remained constant20,26,27. This proposition is supported by several experimental studies using chemostat16,28,29. Many mathematical studies also demonstrate that the coexistence of many species is extremely unlikel ...
Galapagos vertebrates: endangered status and conservation actions
... habitat loss and/or fragmentation; arrival of introduced species that are predators or disease vectors, or that compete for habitat or food; ...
... habitat loss and/or fragmentation; arrival of introduced species that are predators or disease vectors, or that compete for habitat or food; ...
Community monopolization: local adaptation enhances priority
... Figure 1. We developed an individual-based model of community assembly in a three-patch, two-species metacommunity. (a) Two initially equivalent species with traits matching the environment fill two patches, each with 1000 microsites and an environmental value (e) of 0.4 (symbolized in yellow). A th ...
... Figure 1. We developed an individual-based model of community assembly in a three-patch, two-species metacommunity. (a) Two initially equivalent species with traits matching the environment fill two patches, each with 1000 microsites and an environmental value (e) of 0.4 (symbolized in yellow). A th ...
Community monopolization: local adaptation enhances priority
... Figure 1. We developed an individual-based model of community assembly in a three-patch, two-species metacommunity. (a) Two initially equivalent species with traits matching the environment fill two patches, each with 1000 microsites and an environmental value (e) of 0.4 (symbolized in yellow). A th ...
... Figure 1. We developed an individual-based model of community assembly in a three-patch, two-species metacommunity. (a) Two initially equivalent species with traits matching the environment fill two patches, each with 1000 microsites and an environmental value (e) of 0.4 (symbolized in yellow). A th ...
The Serengeti food web: empirical quantification and analysis of
... 3. We study the topological changes in this food web that result from the simulated IUCN-based species-loss sequence representing current species vulnerability to human disturbances in and around this savanna ecosystem. We then compare this realistic extinction scenario with other extinction sequenc ...
... 3. We study the topological changes in this food web that result from the simulated IUCN-based species-loss sequence representing current species vulnerability to human disturbances in and around this savanna ecosystem. We then compare this realistic extinction scenario with other extinction sequenc ...
Authorised - ACT Legislation Register
... 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 ...
Population size and the risk of local extinction: empirical evidence
... Stöcklin 1997) for population size, have also reported negative effects of small population size on survival. In contrast, Husband and Barrett (1996) found no such relationship in Eichhornia paniculata, an aquatic plant of ephemeral pools in north-east Brazil, which they attributed to the frequent ...
... Stöcklin 1997) for population size, have also reported negative effects of small population size on survival. In contrast, Husband and Barrett (1996) found no such relationship in Eichhornia paniculata, an aquatic plant of ephemeral pools in north-east Brazil, which they attributed to the frequent ...
Introduction: - Library - Conservation International
... habitat distribution & ecosystem composition and structure within Key Biodiversity Areas Conservation Outcome: ‘Areas Protected’ Quantity and quality of habitat is among the indicators most highly correlated with the ability of species to persist an a site. If habitat quality and ecosystem processes ...
... habitat distribution & ecosystem composition and structure within Key Biodiversity Areas Conservation Outcome: ‘Areas Protected’ Quantity and quality of habitat is among the indicators most highly correlated with the ability of species to persist an a site. If habitat quality and ecosystem processes ...
Introduction: - Library - Conservation International
... habitat distribution & ecosystem composition and structure within Key Biodiversity Areas Conservation Outcome: ‘Areas Protected’ Quantity and quality of habitat is among the indicators most highly correlated with the ability of species to persist an a site. If habitat quality and ecosystem processes ...
... habitat distribution & ecosystem composition and structure within Key Biodiversity Areas Conservation Outcome: ‘Areas Protected’ Quantity and quality of habitat is among the indicators most highly correlated with the ability of species to persist an a site. If habitat quality and ecosystem processes ...
Chapter 50 Conservation Biology
... – Biodiversity brought about by evolutionary change has value in and of itself. Mader: Biology 8th Ed. ...
... – Biodiversity brought about by evolutionary change has value in and of itself. Mader: Biology 8th Ed. ...
A conceptual framework for marine biodiversity and ecosystem
... to remain unmodified over the long term. For example, the Baltic Sea was formed only after the last glaciation some 10,000 years ago and gained its current brackish water conditions no more than 7000 years ago; it is still undergoing dramatic abiotic and biotic changes (Voipio 1981). Change can be o ...
... to remain unmodified over the long term. For example, the Baltic Sea was formed only after the last glaciation some 10,000 years ago and gained its current brackish water conditions no more than 7000 years ago; it is still undergoing dramatic abiotic and biotic changes (Voipio 1981). Change can be o ...
Title: A new idea on the evolution of biodiversity
... The carrying capacity, however, should not be seen as a static threshold, but rather as a dynamic range of density that regulates the number of individuals in populations. Without the constraint of this ecological edge the population would increase following an exponential growth, with an intrinsic ...
... The carrying capacity, however, should not be seen as a static threshold, but rather as a dynamic range of density that regulates the number of individuals in populations. Without the constraint of this ecological edge the population would increase following an exponential growth, with an intrinsic ...
Biodiversity - University of London International Programmes
... Activity 2: Patterns in the spatial distribution of plants................................. 95 Activity 3: Naturalness and equilibrium........................................................ 100 Activity 4: Population dynamics models........................................................ 100 Activi ...
... Activity 2: Patterns in the spatial distribution of plants................................. 95 Activity 3: Naturalness and equilibrium........................................................ 100 Activity 4: Population dynamics models........................................................ 100 Activi ...
The evolutionary consequences of biological
... most introduced populations retained 80% or more of the genetic variation present in native populations (Fig. 1). In some cases, substantial genetic diversity may be retained if the introduced population quickly grows to substantial numbers. In Britain, the introduction history is well-known for som ...
... most introduced populations retained 80% or more of the genetic variation present in native populations (Fig. 1). In some cases, substantial genetic diversity may be retained if the introduced population quickly grows to substantial numbers. In Britain, the introduction history is well-known for som ...
21 | CONSERVATION AND BIODIVERSITY
... Most of these “invisible” species that will become extinct currently live in tropical rainforests like those of the Amazon basin. These rainforests are the most diverse ecosystems on the planet and are being destroyed rapidly by deforestation, which biologists believe is driving many rare species wi ...
... Most of these “invisible” species that will become extinct currently live in tropical rainforests like those of the Amazon basin. These rainforests are the most diverse ecosystems on the planet and are being destroyed rapidly by deforestation, which biologists believe is driving many rare species wi ...
Mammals on mountainsides: elevational patterns of diversity
... richness appear to be correlated closely with area or temperature (or with total energy sensu Currie, 1991). There are also some important differences among the case studies. Some ecological relationships appear to be region- or taxon-specific. The abundance of earthworms and the importance of these ...
... richness appear to be correlated closely with area or temperature (or with total energy sensu Currie, 1991). There are also some important differences among the case studies. Some ecological relationships appear to be region- or taxon-specific. The abundance of earthworms and the importance of these ...
Bumblebees
... insects are in decline and urgent action is required to save them. Bumblebees have undergone a rapid decline in their range and population. There are 25 species native to the UK, but three are now extinct and six species have declined by at least 80% in recent years. This is largely due to changes i ...
... insects are in decline and urgent action is required to save them. Bumblebees have undergone a rapid decline in their range and population. There are 25 species native to the UK, but three are now extinct and six species have declined by at least 80% in recent years. This is largely due to changes i ...
Qualitative Insight Into Public Knowledge of, and
... While social research continues to document high levels of public concern with environmental issues, substantial evidence also continues to accumulate as to the low levels of public environmental knowledge. As examples, research has revealed public misunderstanding as to the details of natural ecolo ...
... While social research continues to document high levels of public concern with environmental issues, substantial evidence also continues to accumulate as to the low levels of public environmental knowledge. As examples, research has revealed public misunderstanding as to the details of natural ecolo ...
Extinction order and altered community structure
... Rapid rates of global biodiversity loss are intensifying the need to understand the consequences for the functioning of ecosystems (Purvis & Hector 2000). Most studies to date have focused on the relationship between species richness and function, without including other components of biodiversity ( ...
... Rapid rates of global biodiversity loss are intensifying the need to understand the consequences for the functioning of ecosystems (Purvis & Hector 2000). Most studies to date have focused on the relationship between species richness and function, without including other components of biodiversity ( ...
Some Principles of Conservation Biology, as They Apply
... conservation problems are inherently transdisciplinary, conservation biology must involve not only biologists, but also geographers, sociologists, economists, philosophers, lawyers, political scientists, educators, artists, and other professionals. A distinguishing feature of conservation biology is ...
... conservation problems are inherently transdisciplinary, conservation biology must involve not only biologists, but also geographers, sociologists, economists, philosophers, lawyers, political scientists, educators, artists, and other professionals. A distinguishing feature of conservation biology is ...
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.