Biodiversity & Conservation; Climate change Outline: Patterns and controls on diversity Species extinctions Overexploitation Habitat destruction – fragmentation Introduced species Conservation and protected areas Climate change Readings: 26, 28 and 29

Large-scale patterns of biological diversity

invertebrates

Geographic patterns in species richness

Species richness correlates with climate

Extinctions of Large Animals Recent extinctions have primarily affected large animals (which are more profitable prey for hunters) The timing of extinctions in different regions has coincided with the arrival of humans (note absence of extinctions in Africa)

Caribbean monk seal Monachus tropicalis Yangtze dolphin Carolina parakeet

Nile perch Deliberately introduced to Lake Victoria (east Africa) in the 1960s to provide food for local fishermen. Has caused the extinction of at least 200 species of fish that were endemic to the lake

Hot spots of biodiversity: high overall biodiversity (1500 or more endemic plant species) significant impacts from human activities

Minimum viable population Minimum dynamic area

Bighorn sheep

Global climate change

The effects of global climate change have been most pronounced at the poles

Effects of climate change

Precipitation patterns will also change; some areas will get more precipitation, others less Temperate countries may become more agriculturally productive; tropical countries will most likely become less productive  Food production may increase in developed countries but these already have an overabundance of food; in third world countries, food shortages will worsen Effects of climate change

The current distribution of Douglas fur (green), regions where Douglas fur is currently found but is predicted to be unable to grow by the end of the 21st century (red), and regions where Douglas fur cannot grow at present but is predicted to be able to grow by the end of the 21st century (blue). Changes to zones where species can live

Dawn redwood Metasequoia glyptostroboides During the most recent glacial cycle of cooling and warming, this species went extinct in most parts of the world because it could not disperse fast enough to keep up with shifting climate zones. In the 21st century, the rate of global warming is expected to be times faster than at the end of the last ice age. Many species will be unable to relocate fast enough to avoid extinction without human assistance.