Features of r-selected and K-selected species

short lived

r-selected species

small body size

r-selected species

few offspring

K-selected species

high competitive ability - may be dominant species in the ecosystem

K-selected species

large amount of parental care - high investment in young - few young so high chance of survival is important

K-selected species

large body size

K-selected species

long life cycle - usually number of years before mature and able to reproduce

K-selected species

low dispersal ability - colonisation of new habitats less frequent

K-selected species

population size more constant

K-selected species

tend to be highly specialised so less resistant to environment change - prone to becoming extinct in changing environment eg polar bears and global warming

K-selected species

typically occur in stable habitats that remain relatively undisturbed for many years eg oak trees in a forest

K-selected species

able to disperse rapidly and colonise new habitats

r-selected species

low competitive ability - unlikely to become dominant

r-selected species

not specialised o adaptable to change in environment - can evolve rapidly eg antibiotic resistance in bacteria

r-selected species

often inhabit unstable or short-lived habitats eg weeds in a ploughed field

r-selected species

population size very variable

r-selected species

reproduce rapidly with usually many offspring

r-selected species

very little parental care

r-selected species