Extinction and environmental change – adapt, shift range or die out; mass extinctions
BiologyEvolutionAges 17–18
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Sign in to playSix species sharing a landscape face climate warming, habitat loss or a sudden catastrophe. Set the rate of change and each species' generation time and genetic variation, and see which species adapt in time, which must shift their range and which go extinct. The Deep time screen compares background and mass extinction rates, counts extinctions and new species over tens of millions of years, and shows the adaptive radiation of the surviving lineages.
Lesson: Extinction: environmental change, rate of adaptation, background and mass extinction, adaptive radiation
What it shows
Species survive environmental change in three ways: they adapt by natural selection, they move to places that still suit them, or they decline and go extinct. How fast a species can adapt depends on its genetic variation and on its generation time, because selection acts once per generation. This model follows six species while the climate warms, habitat is lost or a catastrophe strikes. A second screen zooms out to millions of years: background extinction is balanced by new species, a mass extinction removes most of them, and the surviving lineages radiate into the empty niches.
How to use
On the Populations screen choose a type of change and press Run. Watch the dots move uphill as species shift their range, and read the table: which species keep up, which decline, which go extinct. Pick a species and change its Generation time or Genetic variation, then press Reset to compare. On the Deep time screen choose one of the Big Five extinctions, press Run and watch the diversity curve fall and recover.
Parameters you can change
- Screen Populations under environmental change, Deep time: mass extinctions
- Type of environmental change Climate warming, Habitat loss, Warming and habitat loss, Sudden catastrophe
- Rate of warming 0–6 °C/century
- Rate of habitat loss 0–40 %/century
- Severity of the catastrophe 10–95 %
- Background extinction rate 0.05–0.5 per species per Myr
- Maximum speciation rate 0.2–1 per species per Myr
- Share of species lost in the mass extinction 0–96 %
- Which species are more at risk Random, Large-bodied species more at risk
Questions to explore
- Why can a beetle keep up with fast warming when an oak tree with more genetic variation cannot?
- How does habitat loss make warming more dangerous for species that need to shift their range?
- After a mass extinction, why do new species appear faster than they did before the event?
