Human impact and population (WIP)

Natural selection

1- factors like predators, shortage of food and diseases determine survical so only the best adapted will survive. adaptations caused by random mutation.

Survivors are more likely to reproduce and pass donew favourable alleles

What is the global ecosystem

gthe earths entire collection of living things and the environment in which they live

What causes extinction

destruction of habitats (eg from agriculture, forestry, mining, urban developemnt

stress on most productive and diverse aread like coral reefs

Examples of alien species introduc5tion

Mink, cane toads, grey squirrel, rhododendron

example of species mortality

competition, disease

example of ecosystem degradation

farmland monoculture, hedgerow removal, desertification

example of ecosystem conversion

urbanisation, deforestation

example of environmental contamintation

PCBs, eutrophication, air pollution

What is fragmentation

Habitat fragmentation is when a habitat is broken up into smaller fragments, or sections. This results in habitats being too small or too far apart for organisms to move between