Chapter 10 Flashcards
What is a species’ realized niche?
The range of abiotic and biotic conditions under which a species persists is its realized niche.
The fundamental niche of a species is the range of abiotic conditions under which species can persist.
What two environmental factors are commonly used when modeling the niche of a terrestrial species?
Temperature and precipitation
What predictions can you make about the distribution of the scarlet monkeyflower in response to global warming?
Scarlet monkeyflower excel at low elevation, with global warming itll be pushed to higher elevations and the distribution will decline.
Why are endemic species at a high risk of extinction?
When habitats of endemic species are damaged by various human activities, the distribution ranges and population sizes of the species will be reduced, leaving them vulnerable to extinction at a much higher rate than other comparable species. Endemic usually are native to one area
Why is the realized niche considered to be a subset of the fundamental niche?
The fundamental niche is the area of a species’ livable range of abiotic conditions, but the realized niche is the area other organisms do not prevent the species from occupying. Realized is found as a result of limiting factors in the environment
Fundamental is the range of abiotic conditions under which species can persist. But realized is the range of conditions under which a species persists.
The range of suitable abiotic conditions where individuals can persist represents the fundamental niche of a species. The subset of conditions where a species actually persists due to biotic interactions is known as the realized niche.
How might we use an ecological niche model to predict the future spread of the emerald ash borer?
identify places to monitor in North America that have habitat characteristics similar to the emerald ash borer’s native range. Ex. biologists have set up traps containing beetle sex attractants to estimate the abundance and density of beetles in the area. Reason for this is to determine the amount to see future spread. These properties are typically measured by using a variety of survey techniques, including area- and volume-based studies, line-transect studies, and mark-recapture studies.
One effort to reduce the abundance and geographic range of the emerald ash borer is by introducing a natural enemy that controls the pest in its native range in Asia
The American bullfrog is native to eastern North America, but it has been moved by humans and now thrives in western North America. What does this suggest about the cause of the bullfrog’s historical geographic range?
The bullfrog lacks dispersal corridors with suitable habitat between east and west coast populations. The bullfrog’s realized niche includes its native range and much of the habitat along the west coast. Bullfrog might have environmental factor
Corridor : clearly defined geographical space that is governed and managed over the long term to maintain or restore effective ecological connectivity.
With continued global warming, what dispersal barriers might arise for reptiles that try to move to higher latitudes?
Areas they can’t cross. For example, human activities such as road building and forest clearing have created barriers to dispersal for some species. Humans have also assisted in the dispersal of plants and animals for thousands of years. Occasionally, individuals cross formidable barriers and disperse long distances without assistance from human
In a forest, why might you observe young maple trees exhibiting a clustered pattern of dispersion?
Some species of trees form clusters of stems because a parent tree gives rise to offspring by sending up new stems from its roots, a form of vegetative reproduction. As a result, we commonly see clusters of aspen trees that are composed of a parent tree surrounded by its offspring. many species will form clusters surrounding areas with rich resources.
Why do birds have their highest densities near the center of their geographic range?
The biotic and abiotic conditions at the center of the birds’ geographic range are most ideal and support more individuals compared to the periphery (edge of earth). As one moves closer to the periphery of the geographic range, biotic and abiotic conditions become less ideal and support fewer individuals. In the center more breeding is done.
Why might you expect to find a negative correlation between adult body size and population density in fish?
In species that live at high population densities, individuals have limited space for existing and obtaining resources, which restricts growth of individuals to a small body size. Larger animals require more space to support their metabolism.
How might the presence of a predator alter the predictions from an ideal free distribution?
Ideal free distribution is when individuals distribute themselves among different habitats in a way that allows them to have the same per capita benefit. The presence of predators or of a territory owner prevents species from moving into a high-quality habitat.
