Ch 4 Qs Flashcards
Insects are one of the most species-rich groups on the planet, and are ecologically important. List at least three reasons discussed in class that makes them so important.
Composting, biodiversity, pollination, regulators of pest populations, dung beetles by taking feces from mammals and burying it in the soil which enriches the soil.
What is resource partitioning, and how can it lead to competitive exclusion / specialization of species within biological communities?
Resource partitioning is how organisms in an ecosystem divide the resources in their given ecosystem amongst each other. It leads to competitive exclusion and specialization of species within biological communities because if two organisms need the same resource and there is not a lot of it, the larger more powerful organisms will dominate and exclude the smaller and weaker organisms from obtaining that resource. The specialization is caused by the organisms using one resource while resource partitioning, which makes them highly dependent on that resource and not on other resources.
Why are beavers considered keystone species in the Nature Preserve?
By constructing dams, the beavers create an ecosystem used by a wide variety of, thus making them a keystone species.
What is the difference between species richness and species evenness, and why are they both important components of diversity?
Species richness is the number of different species in an ecosystem, while species evenness is a measure of the comparative abundance of all species in an ecosystem. These are both important components of diversity because they both measure the relative amount of biodiversity in the ecosystem and it gives scientists the ability to advocate for and research solutions.
How many species have been formally described by science?
1.5 million species
How many are likely to actually exist on our planet?
About 8.7 million species
Why is genetic diversity important for natural populations?
Three reasons for why genetic diversity is important for natural populations: Genotypes partly determine organisms’ physical form and function, diversity within populations reduces potentially deleterious effects of breeding among close relatives, and the final one is genetic diversity is the primary basis for adaptation to future environmental uncertainty
