Biology 1 Lecture Thanksgiving - Biodiversity Part 1

Tree of life

What can biodiversity be thought of as?

Total genetic information contained within all individuals of a population, species, or group of species

Define genetic diversity

Number and relative frequency of all genes and alleles present in a species

How is genetic diversity measured?

Number and relative frequency of all genes, number of trophic levels

List 2 ways that communities vary

Genetic variation plus interactions with the abiotic environment

What is ecosystem diversity?

5-100 million, 1.5 million

What is the estimated # of species on Earth? How many have been discovered and described?

Bacteria and archaea

What lineages of species are particularly poorly known?

B: highest richness and evenness

Which community has highest diversity?
A) 6 species, poorly spread
B) 6 species, 3 organisms in each species
C) 5 species, 4 organisms in each species

High species richness and evenness

What does a high Shannon index indicate?

Number of species present in a given community

Define species richness

Weighted measure that incorporates a species relative abundance (evenness)

Define species diversity

Richness and evenness

What do biologists often combine to calculate species diversity?

Tropical rain forest

Which ecosystem represents just 7% of Earth's land area but is thought to contain at least 50% of all species present?

Northern Africa deserts, low primary productivity due to lack of plants and precipitation

What area has the lowest primary productivity and mammal diversity? Why?

Diversity and abundance of plants and animals

What is strongly correlated?

Longer season, can differentiate niches and decrease competition

What does recent research suggest as a potential reason that tropical forests have greater diversity?