An ecologist studying plants in the desert performed the following experiment. She staked out two identical plots, which included a few sagebrush plants and numerous small, annual wildflowers. She found the same five wildflower species in roughly equal numbers on both plots. She then enclosed one of the plots with a fence to keep out kangaroo rats, the most common grain-eaters of the area. After two years, to her surprise, four of the wildflower species were no longer present in the fenced plot, but one species had increased dramatically. The control plot had not changed. Using the principles of ecology, propose a hypothesis to explain her results.
Explanation:
- This example highlights the impact of plant predation on species selection. In the fenced off plot animal predation is not a factor on plant selection.
- In this case plants will compete for resources only with each other and in this case one plant had a selective advantage over the other 3 species of plants. In the plot exposed to animal predation the ratio of the four species is equal.
- This is likely do to an increased preference of animals for the plant species that dominates in the fenced off plot and/or anti-animal predation tactics by the other three species.
a.Hypothesis: kangaroo rats are keystone species
-Reintroduce kangaroo rats (and the other locally extinct species)
-Should observe equilibrium re-established
b.Hypothesis: kangaroo rats exert top-down control on community
-Reintroduce kangaroo rats (and other locally extinct species)
-Increase kangaroo rat population in other plot
-Decrease (but don't eliminate) kangaroo rat population in other plot
c.Hypothesis: Locally extinct species inferiorly competed with the extant species of plant
-Remove surviving species from other plot (and remove kangaroo rat population)
Answer:
The physical and biological changes that confirm climate warming include the rate of retreat in glaciers around the world, the intensification of rainfall events, changes in the timing of the leafing out of plants and the arrival of spring migrant birds, and the shifting of the range of some species.
Explanation:
Answer:
The reason for this is that both moss and fern species are relatively primitive plants that are only Imperfectly adapted to a terrestrial environment. ferns have both roots and vascular tissue and therefore, can grow larger than moss species, but like the mosses, ferns require water for reproduction.
Answer:
Whales are mammals and do not have gills, so they cannot take the dissolved oxygen that is in the water and turn in into a oxygen that they can breath.
Explanation:
Answer:proteins
Explanation:
Proteins are large biopolymer molecules that are made up of repeating monomer units called amino acids.
