Polar fish experience lower mortality than tropical fish, allowing them to delay reproduction until later in life when they are larger and can produce more eggs, according to a study by Mariana Álvarez-Noriega at Monash ...
Plants & Animals
May 25, 2023
0
23
In the summer of 2021, Canada's all-time temperature record was smashed by almost 5℃. Its new record of 49.6℃ is hotter than anything ever recorded in Spain, Turkey or indeed anywhere in Europe.
Earth Sciences
Apr 30, 2023
45
750
California sea lions have managed to maintain—and, in the case of males, increase—their average body size as their population grows and competition for food becomes fiercer. This is in contrast to other marine mammals, ...
Plants & Animals
Apr 27, 2023
0
76
Increasing either temperature or nutrients can hurt ecosystems by destabilizing food webs, which are all of the interconnected food chains that make communities behave the way they do. When temperature and nutrients increase ...
Ecology
Apr 26, 2023
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8
Foraging greater mouse-eared bats invest more resources in hunting large, difficult-to-catch, ground-dwelling insects over smaller, more easily caught flying insects, despite a greater risk of failure.
Plants & Animals
Apr 18, 2023
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308
The small size and isolation of the endangered population of Southern Resident killer whales in the Pacific Northwest have led to high levels of inbreeding. This inbreeding has contributed to their decline, which has continued ...
Ecology
Mar 20, 2023
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80
Wheat, which includes bread wheat and its relatives, is a staple food crop that feeds about 35% of the world's population. As one of the first ancient crops to appear in the Fertile Crescent, wheat has been cultivated for ...
Evolution
Mar 20, 2023
0
123
The western chimpanzees of Guinea are threatened by mining activities. Using a novel genetic approach, UZH researchers and an international team have collected information on population size and community structure of the ...
Ecology
Mar 16, 2023
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3
The Chinese sturgeon (Acipenser sinensis) is the largest anadromous fish in the Yangtze River and is considered a critically endangered species with only one spawning ground. Additionally, it has failed to spawn in recent ...
Plants & Animals
Mar 14, 2023
0
2
As the planet warms, animals that breed in the Arctic are at particular risk. But a new study reported in Current Biology on March 1 offers some encouraging news: in an apparent reaction to pressures along their former migratory ...
Plants & Animals
Mar 1, 2023
0
117
In population genetics and population ecology, population size (usually denoted N) is the number of individual organisms in a population.
The effective population size (Ne) is defined as "the number of breeding individuals in an idealized population that would show the same amount of dispersion of allele frequencies under random genetic drift or the same amount of inbreeding as the population under consideration." Ne is usually less than N (the absolute population size) and this has important applications in conservation genetics.
Small population size results in increased genetic drift. Population bottlenecks are when population size reduces for a short period of time.
Overpopulation may indicate any case in which the population of any species of animal may exceed the carrying capacity of its ecological niche.
This text uses material from Wikipedia, licensed under CC BY-SA
