Flashcards in L11 - Biogeography and Biomes Deck (20):
Who was the first person to attempt to define global bioregions?
Philip Lutley Sclater - 1858
- Expert on tropical birds from Americas
Who can be considered the 'founding father' of biogeography?
Alfred Russel Wallace - 1878
What are the modern biographic provinces
What are the two main types of Historical Biogeography?
Vicariance Biogeography - The geography of barriers
Dispersal Biogeography - The geography of dispersal
Give an example of historical biogeography?
Arid vegetation separated by tropical rainforest.
List key barriers
- Continental drift
- Ecosystem change leaving species isolated
- Impassible areas; mountains, deserts, oceans...etc
- Rising and falling sea level
List key dispersal mechanisms
- Continental drift
- High mobility as a species e.g. Flight
Main Cenozoic 'docking events'
50 mya - India-Southern Asia
20 mya - Africa-Southwestern Asia
8 mya - Africa-Southern Europe
3.5 mya - South America-North America
Define a biome
"A biological subdivision that reflects the ecological and physiognomic character of the vegetation. Biomes are the largest geographic biotic community that is convenient to recognize"
- Defined by dominant type of natural vegetation
- Many controlling factors
- Independent from biogeographic realms
Name key controls effecting biome distribution
- Length of growing season
- Altitude and topography
- Soil Fertility
- Wind Patterns
Why are the Tropics of Cancer and Capricorn at 23.5o?
- Reflects tilt of the Earth
- Limit of when the Sun may appear directly overhead
Name the 14 biomes
Tropical & Subtropical
- T & S Moist broadleaf forest
- T & S Dry broadleaf forest
- T & S Coniferous forests
- T & S Savannah
- Temperate grassland
- Alpine grassland
- Temperate coniferous
- Temperate broadleaf
- Flooded grassland
- Boreal Forest
How many freshwater biomes are there
12 - Split into 'lentic' (still) and 'lotic' (flowing)
What is an endolithic biome?
The microscopic biomes within rock
How many marine biomes are there
Give an example of a diffuse biome transition?
Give an example of a sharp biome transition
Temperature-controlled divide between Boreal Forest and Tundra - permafrost
What % of the Earth surface was covered in ice 10,000 years ago?
Today - 10%
What impact does glaciation have on desert size?