Flashcards in Observing And Mapping Biodiversity Deck (24)
What are the 3 methods for linking past climates to biodiversity?
2. Biological materials
3. Stable isotopes
What is the historical record of the earth (3 points)
1. Long warm tropical/semi tropical climate
2. Lowering of temp
3. Temperate cycles over past 1.6my, including glaciations
What are the 3 causes of glaciation?
What is eccentricity and how long is it’s cycle?
Eccentricity is that the earths orbit around the sun is not central, it is an oval shape, 100,000 year cycle
What is obliquity and how long is it’s cycle?
The angle of the tilt of the earth, between 24.5 and 22.1 degrees, 41,000 year cycle
What is precession and how long is it’s cycle?
The angle of the earths axis relative to certain stars that remain in the same position, 22,000 year cycle
What does ‘changing species affinity’ mean?
When climates change and species that were once present no longer are and new ones move in
Give an example of changing species affinity to indicate climate change
Sheppey (London clay)
- 65mya palm trees
- 40mya warm temperate forest trees (pine)
- 20mya modern flora (sycamores beech oak)
What are Pleistocene glaciations?
The multiple glaciations over the last 2my, advances and retreats every 100,000
What is amelioration?
Is the reinvasion of species after the retreat of glaciers from an area
What are foraminifera?
Small planktonic animal that could right in warmer temperatures and left in cooler temperatures
What is a refugia?
A refugia is a location which supports an isolated or relict population of a once more widespread species
What is a relict population?
A relict population is a population that was once more widespread but now occurs in a restricted area
Give examples of land bridges
1. English Channel
2. New-Guinea Australia
3. Bering strait
What types of barriers are there?
Oceans, mountains, and temperature extremes
What does isolation lead to
How many biogeographic regions are there?
What are the 3 tropical regions called?
What is the order of biodiversity of the tropics
How many eco regions are there?
What are ecoregions?
Eco regions are areas that have distinct biotas (the animal and plant life of the region), they have a mixture of plants and animals that can’t be found anywhere else on earth
What are biodiversity hotspots?
regions that have high priority to conservation, because of organisms only being found in that region, or because of rapid habitat loss due to high human population growth
How many hotspots are there