Lecture 12 - evolution & conservation

Question 1

What is conservation?

Answer 1

area of biology that looks at how species are affected by changes in the world. It goes on to explore how to protect these environments & species

Question 2

What can threaten conservation?

Answer 2

• human activities change the environment
• habitat loss
• climate change
• pollution
• invasive species

Question 3

What is the consequence of change to the environment?

Answer 3

The change in the environment can lead to the organisms in that area who are well-adapted to the first environment struggling in the new environment. This can lead to more predation or less reproduction and as a result can lead to reduced population sizes

• reduced population sizes
• extinction of populations
• extinction of species
• loss of ecosystems

Question 4

How much has species declined?

Answer 4

World Wildlife Fund (WWF) found that there was 50-67% decline in species from sample of 4005 species by 2018 compared to 1970

Question 5

What are examples of extinction due to a decrease in population?

Answer 5

• Dodo bird - flightless pigeon (extinct in the 17th century)
• Chinese river dolphin - suffered from pollution in river
• Great auk (penguin-like)

Question 6

What was the biggest factor driving extinction?

Answer 6

loss of habitat

Question 7

How can we identify correlates of extinction?

Answer 7

• are some species more likely to become extinct than others
• are species at threat randomly distributed
• does this depend on their ecology
• does this depend on where they live

Large, tasty, flightless animals more likely to be driven extinct

Question 8

What is a phylogenetic niche conservatism?

Answer 8

• an imprint at evolutionary outcome
• species inherit their niches from ancestors
• closely related species are ecological similar
• share similar life-histories

Question 9

What are examples of phylogenetic niche conservatism?

Answer 9

• old world leaf warblers
• very similar in appearance
• also similar in ecology
• insectivorous
• feed on trees
• short-lived
• many co-occur

As a result, loss of one species, likely to lead to the outer

Question 10

What are the consequences of phylogenetic niche conservatism?

Answer 10

• closely related species share similar levels of threat, because they are ecologically similar
• low rates of adaptability - conservatism is a consequence of this
• low rates of evolution - also conservatism results from this

Question 11

Describe phylogenetic niche conservatism & extinction in mammals

Answer 11

• IUCN threat - measure of how likely populations are to become extinct in coming years
• life history & ecological variables
• chosen carefully
• used statistical analysis to compare threats and these variables

Question 12

What correlates with extinction threat?

Answer 12

• geographic range size
• body size
• gestation time
• age at sexual maturity
• tropic level
• population density
• human footprint
• human density

Question 13

What is phylogenetic conservatism?

Answer 13

measured by looking to see whether evolutionary distance correlates with differences in traits

Question 14

What is included when considering the level of phylogenetic conservatism?

Answer 14

• geographic range size - NO
• body size - YES
• gestation time - YES
• trophic level - YES
• IUCN threat - YES

Question 15

Is phylogeny a good predictor of extinction threat?

Answer 15

moderately good - thus is a consequence of shared evolutionary history

Question 16

Describe niche conservatism in mammals

Answer 16

• further analysis by Cooper
• measured & compared rates of evolution across groups & over the globe
• evolution is faster outside of the tropics
• Niche conservatism is greater in the tropics

Question 17

What is phylodiversity?

Answer 17

• some areas & groups are more or less adaptable in the face of threats
• some areas contain more unique species than other
• phylogenies contain unequal distribution of species
• based on phylogenetic information can prioritise conservation

Question 18

What is phylogenetic diversity?

Answer 18

total amount of history shared by a group of species

Question 19

How can phylogenetic diversity information be used?

Answer 19

• record the species present in a set of areas
• generate a phylogeny for the species
• calculate phylogenetic diversity
• prioritise accordingly (when deciding what to conserve)

Question 20

What is an example of how phylogenetic diversity information be used?

Answer 20

phylogenetic diversity & species richness in Australian Frogs

Question 21

How important is phylogeny in prioritising species?

Answer 21

• phylogeny should be an important consideration in deciding which species to conserve
• conservation should aim to conserve as wide a range of phylogenetic diversity as possible
• focus away from species rich groups in which individual species are threatened
• focus on evolutionarily distinct species
• this is because phylogenetic diversity correlates with genetic & functional diversity