Unit 3.2 ~ K-selected & r-selected species
Quality vs. Quantity
K-selected - “quality”
- Few offspring, heavy parental care to protect them
- Usually reproduce many times
- Ex: most mammals, birds
- Long lifespan, long time to sexual maturity = low biotic potential = slow pop. growth rate
- More likely to be disrupted by environmental change or invasive
R-selected - “quantity”
- Many offspring, little to no care
- May reproduce only once
- Ex: insects, fish, plants
- Shorter lifespan, quick to sexual maturity = high biotic potential = high pop. growth rate
- More likely to be invasive
- Better suited for rapidly changing environmental conditions
K-selected
- Low biotic potential (rep. rate) = hard for pop. to recover after a disturbance (env. change)
- High parental care means death of parent = death of offspring
- Invasives (usually r) outcompete for resources with high biotic potential & rapid pop. growth
- Less likely to adapt & more likely to go extinct
R-selected
- High biotic potential (rep. rate) = more rapid pop. recovery after disturbance
- Low parental care means death of parent doesn’t impact offspring
- Not as impacted by invasive species since their pop. grow quickly
- More likely to be the invasive
- Larger pop. & faster generation time = higher chance of adaptation & lower chance of extinction