Conservation Biology Exam 1

About how many discovered species are there?

2.5 million

Fish are the most ___ type of vertebrates

diverse

What is biodiversity?

The variety of life at all levels within a defined area (not just species, its molecular, etc)

What’s the pace of new species descriptions?

About >16,000 new species a year

What are the five ways to generate estimates of the number of undescribed species?

Use ratios and extrapolate, body size/diversity relationships, taxonomy/diversity relationships, species area curves, and time species accumulation curves

A biodiversity hotspot is

a region with many species that are threatened by human activity - any place with high species richness per unit area

Why is it that hotspots can create both a bad and good news situation?

On the good side, ecosystems thrive in hotspots but if something happens it will all be wiped out

We are currently in a ____. Which is the sixth mass extinction of at least 100 described species going extinct since the 1600s

biodiversity crisis

Conservation biology is a ____ principle.

subjective

What are the six tenets conservation bio has, written by Soule in 1985?

1. Diversity of species should be preserved

2. Extinction of species should be avoided

3. Ecological complexity should be maintained

4. Evolution should continue

5. Biodiversity has intrinsic value

6. Native diversity > non native diversity

What are the three ethical involvements contributing to US Conservation biology?

1. Preservation ethic: states that intrinsic value of animals is equal to humanity (laid the foundation for national parks)

2. Resource conservation ethic: recognized exploitation (Gifford Pinchot developed ‘the wise use’)

3. Land ethic: humanity is apart of nature and should manage ecosystems to meet biodiversity and human needs (Aldo Leopold stated this)

Other important names for conservation biology include

Rachel Carson (scientifically documented the role of pesticides in loss of bird populations) and Edward Abbey (passionate essayist that ignited the radical environmental movement)

What are the two ways to determine species diversity?

Species richness (how many animals are in an area) and evenness (not just how many animals but also how many types of animals)

A true diversity index includes a combination or richness and evenness using the basic ____ equation.

expected heterozygosity

Richness does not equal diversity, why do we care?

Diff species have diff roles in the ecosystem, so the more diverse, the better an ecosystem functions

How can you determine Shannon diversity?

Through this equation: H= -{ (PaLnPa) + (PbLnPb) + …} where Px is the proportion of individuals from species x (so the number of species divided by the total number of animals)

Species diversity can be measured on different scales; ___ and ___.

Gamma - regional, alpha - local

In calculating species richness mathematically gamma is

the total number of species in the region

In calculating species richness mathematically alpha is

the average number of species per column

In calculating species richness mathematically beta is

the species turnover, so gamma divided by alpha

Individual level heterozygosity is

the proportion of genes that are heterozygous within an individual (higher this means increased fitness)

Population level heterozygosity is

diversity of alleles among individuals withing the population (higher this = increased adaptive potential, disease resistance, etc)

Genetic drift is when

a sub-sectioning of a gene pool occurs resulting in not everything getting passed to the next generation {large populations retain more genetic diversity than smaller populations}

Ne =

the genetically effective population size and it matters more than the total population (N)

Introgression is

the transfer of one species genes into another, like bacterial genes into humans

Outbreeding depression is

deleterious consequences of crossing on mating preference (think about the grolar bear)

Inbreeding depression is

reduction of fitness through inbreeding

What do phylogenetic species concept result in?

Splitting

What are some problems with determining species?

Divergence time is problematic because the speciation clock isn’t a constant rate, phenetic approaches is unreliable because of convergent evolution (ex: African and Asian elephants are diff species but look the same), and reproductive isolation can be tricky because many diff species can produce viable hybrids

What is background extinction rate?

The average rate of extinction over geological time prior to human influence

The average species last about ___ million years. This means you lose about 1-10 species per year out of the 10 million species

1-10

How many mass extinctions have occurred in Earth’s history?

Five

Species area relationship is

the statement or conclusion that with all else being equal, the larger habitat area should have greater richness of species

What section of humans were most responsible for extinction in North America?

Pre-historic humans (before european expansion)

The three aspects of habitat alteration are

habitat degradation, loss, and fragmentation

In habitat degradation, what of the three basic needs to complete the life cycle for animals is affected?

Feeding and growing

How can habitat degradation be tested?

growth rates, stress hormone levels, reproductive success and survival. Indirect things can be measured as well but fitness is the best way to test for habitat degradation

What of the three life cycle needs for animals does habitat loss affect?

Reproduction

What is extinction debt?

predicted extinctions that have not yet occurred and it usually is because of habitat loss

Extirpation is

the local extinction of a species in a geographic area but it still exists in other areas

A species that is endemic means?

It is found in only one geographic area

What is “wise use” referring to?

Using natural resources sustainably without causing long term damage

How are pioneer and climax species different?

Pioneer species are the first to colonize disturbed areas, climax species dominate stable ecosystems

Habitat specialist ____ while generalists can ___.

require specific conditions to live in an environment/ live in many environments (no specifics)

What is a movement corridor?

A strip of habitat that allows organisms to move safely between areas