Evolution and Change (Freckleton)

Question 1

Change

Answer 1

-Human activities change the environment that species live in, e.g. habitat loss to crops/buildings.
-Globally, climate change is causing issues. Species can become maladaptive, cannot survive.
Pollution

Question 2

Consequences

Answer 2

• Reduced population sizes,
• Extinction of populations
• Extinction of species (e.g. Great Auk-hunted, eggs taken and eaten; Dodo, hunting; Chinese River Dolphin (freshwater dolphin), pollution).
• Loss of ecosystems

Question 3

Historic vs Current Evolution

Answer 3

Three factors tend to drive extinction; human exploitation, introduced species, habitat loss. Historically tended to be quite equal.
-Currently, habitat loss is the main thing causing extinction

Question 4

Why is evolution important in conservation?

Answer 4

-All species are the outcome of evolution; all new species will be as a result of evolution. Therefore, we need to understand extinction and speciation. When there are limited resource, which species and areas should we conserve?
-Correlates of extinction:
Are some species more likely to become extinct than others. Understanding the correlates of evolution is important
-Phylogenetic niche conservatism

Question 5

Phylogenetic niche conservatism

Answer 5

The key concept in understanding the link between evolution and conservation is Phylogenetic Niche Conservatism. This idea is based on the observation that species inherit their niches from their ancestors. Therefore, when evolution occurs and a new species evolves, although it will be different in some ways from its parent species, in many ways it will be the same. Consequently, because of this closely related species tend to be ecologically similar to each other, as well as sharing many similarities of life-history. The big question is, because of phylogenetic niche conservatism, do closely species share similar likelihood of extinction?

Question 6

Old World leaf warblers

Answer 6

-Very similar in appearance and ecology. Insectivorous and feed in trees. They are short-lived and many co-occur.
All similar because they shared a common ancestor.

Question 7

Consequences of evolution and conservation

Answer 7

• 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 a loss of adaptability.

Question 8

Niche conservatism and extinction in mammals

Answer 8

• Measure of how likely populations are to become extinct in coming years (IUCN threat).
• Life history and ecological variables.
• Statistical analysis was used to compare threats and these variables.

Question 9

Phylogenetic conservatism

Answer 9

Phylogenetic conservatism: measured by looking to see whether evolutionary distance correlates with differences in traits.
-Phylogeny is a moderately good predictor of extinction threat - consequence of shared evolutionary history. If one species is at risk, its likely its close relative are too.

Question 10

Analysis by Cooper, Freckleton and Jetz

Answer 10

• Measured and compared rates of evolution across the group and over the globe.
• Evolution is faster outside of the tropics.
• Evolution is slower in small, wide-ranging and generalised groups.
• Niche conservatism greater in the tropics.
• Niche conservatism lesser in large, small-ranged and specialised groups.

Question 11

Phlodiversity

Answer 11

• Some areas and groups are more or less adaptable in the face of threats. Some areas contain more unique species than others.
• Phylogenies contain unequal distributions of species.
• Based on phylogenetic information an prioritise

Question 12

Phylogenetic diversity

Answer 12

The total amount of history shared by a group of species.

Question 13

How can phylodiversity be used?

Answer 13

• Record the species present in a set of areas.
• Generate a phylogeny from the species.
• Calculate phylogenetic diversity
• Prioritise accordingly.

Question 14

Phylogeny and priotising

Answer 14

• Phylogeny should be an important consideration in decided 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 and functional diversity

Question 15

Predicting speciation

Answer 15

• Speciation is high on islands, initially empty, low levels of predators etc.
• Pat rates of speciation difficult to estimate
• Current areas with high richness - hotspots. Speciation must’ve been high for so many species to be there.

Question 16

Hotspots

Answer 16

• Areas of currently unusually high diversity
• Prioritising these will maximise conservation of phylogenetic diversity.
• Also serve as pools of species in the future –> future speciation.