Factors that affect Biodiversity Flashcards
(20 cards)
An island has many kinds of birds, no native species of snakes, and few large predators. Brown snakes eat bird eggs. What is the MOST likely result of brown snakes being released accidentally on the island?
More snakes and fewer birds
In the past, wild hogs called “javelinas” were seen only in the southern part of New Mexico, javelinas are seen in areas 100 miles further north. What is the MOST likely cause of this expansion?
Environmental conditions have changed
Which statement describes a harmful effect of clearing rainforests for farmland?
Removes valuable habitat for local species
In the 1800’s, domesticated rabbits from Europe were brought to Australia. The rabbit population increased so quickly that it caused severe damage to agriculture and the natural environment. Even though scientists have tried to reduce the rabbit population, it continues to be a problem today. Which statement is the BEST conclusion from this series of events?
Human actions can lead to imbalances in ecosystems.
Non-native plants can take over areas that were once population by native plant species. Which abiotic process is LEAST likely to cause the invasion of non-native plants?
Weathering ( the movement of rocks )
The Miami Blue butterfly is an endangered species in South Florida. Which factor has MOST likely caused the population decline of this butterfly?
increase of number of homes built
What type of population would be MOST affected by a change in the ecosystem?
A beetle that eats only one type of berries
Which action is an example of a change that will MOST likely decrease the population of many species?
The filling in of wetland areas for development of vacations homes
How would a tree falling from the overstory layer MOST immediately affect the surrounding plants in the other 3 layers?
They would have access to more sunlight and more space
What MOST likely caused the loss of the wetlands during this time period?
increase in human population
Acid rain caused by industrial pollution greatly reduces the number of trees in a forested region that is home to a particular species of bird. How might this decrease in the number of trees MOST likely affect the bird population?
The population will decrease due to lack to resources
Since the 1900’s, the human population has increased in Florida. As a result, much of the fresh water that had previously made its way to the Everglades has been diverted for human use. Which would be the MOST likely effect of decreased flows of fresh water on the ecology of the Everglades?
A decrease in the population of native plants and animals
Clear-cutting of old growth forests in Oregon provides lumber for housing. In the process of clear-cutting, plant diversity decreases and some organisms are pushed to extinction. Clear-cutting is an example of
a change in environmental conditions
When humans move into an areas, they sometimes plant grasses, flowers, or trees that are not native to the area. The nonnative species sometimes choke out the native species. Which organism would MOST likely be harmed by a loss of native plants in the area?
The caterpillars that eat only one type of plant.
Fragmentation occurs when a large area of ecosystem is divided into smaller, isolated areas due to deforestation. After fragmentation, changes to the ecosystem can occur. Which is MOST likely an effect of fragmentation on an ecosystem?
Plant species from the deforested area alter conditions at the edge of the fragmented area
Which change in the environment would have a negative effect on the survival of a species in an ecosystem?
introduction of a competing species
Large populations of tortoises inhabited the Galapagos Islands before humans. When humans settled on the islands and introduced goats, the number of tortoise declined. What is MOST likely the explanation for the decrease in the tortoise population?
Goats compete with tortoises for vegetaiton
When a population grows past the ecosystem’s carrying capacity, what happens to the ecosystem?
it decrease the quality of the ecosystem
The MOST common way humans contribute to the extinction of organisms is by
Destruction of habitat
Beavers are known to build dams across rivers and creeks by felling trees and gathering brush and shrubs. The population of beavers in the United States has decrease due to trapping by humans. What is an ecological consequence that MOST likely occurs with a decrease in the beaver population?
A significant decrease in the number of pond habitats.
