Extinction & Rapid Change

Activities to try

1. 1

   The survival race: dial the rate of change against the rate of adaptation

   Why it works: Extinction can happen when environmental change outpaces the generations-long, variation-dependent process of adaptation — a mismatch of rates, not a species simply being weak or failing. Which species survive rapid change depends partly on generation time, available heritable variation, and degree of specialism (as well as factors such as population size and ability to disperse).

   1. Start a scenario where a population with heritable variation faces a changing environment (e.g. gradual warming, or a newly arrived predator) and set the environmental change to a slow rate.
   2. Watch two linked displays at once: the trait distribution shifting generation by generation via selection, and the total population size over time.
   3. Observe that under slow change, selection tracks the environment, the trait distribution slides to match, and the population holds steady — the species survives.
   4. Push the rate-of-change slider higher and watch selection fall behind: the trait distribution cannot shift fast enough, numbers plunge, and the population reaches EXTINCT — the very same species that survived slow change.
   5. Handicap the species using vulnerability levers — long generation time, little genetic variation, high specialism — and compare, in the model, how a slow-breeding, low-variation specialist dies out where a fast-breeding, variable generalist scrapes through at the same rate of change.
2. 2

   Argue the case: interview a conservation biologist or palaeontologist

   Why it works: The argue-from-evidence objective asks learners to turn the rate-race model into a defended explanation of why a given species could not keep pace and why current rates exceed the background rate.

   1. Take part in a role-play interview with a palaeontologist (about the dodo or woolly mammoth) or a conservation biologist (about a species on the brink today).
   2. Respond to the challenge 'Why couldn't it just adapt?' by explaining the rate mismatch and the species' specific vulnerability factors.
   3. Respond to 'Why are today's extinction rates different from normal?' by distinguishing background from mass extinction and naming human drivers (habitat loss, overexploitation, pollution, climate change).
   4. Marshal observations from the survival-race activity into a short, evidence-based argument about whether a named species can keep pace with current change.
3. 3

   Hall of extinction: case gallery and geological timeline

   Why it works: The same rate-mismatch logic explains extinctions across deep time and the present; vulnerability factors help predict which species survive rapid change. Background extinction is a steady ongoing process, distinct from rare catastrophic mass-extinction pulses.

   1. Explore a gallery of extinct and endangered species — dodo, woolly mammoth, thylacine, plus contemporary cases such as amphibians or coral — revealing for each one its vulnerability factors and the specific change that outpaced it.
   2. Place each case on a geological timeline that marks the five past mass extinctions and the current pulse.
   3. For each species, state in your own words what outpaced its ability to adapt and why.
   4. Sort species into higher or lower vulnerability and justify each choice using generation time, genetic variation, and specialism.