Ecology and Adaptation: Summary Notes

Job Opportunity

  • Paid summer work with Dr. Sophie Watson
  • Focus: Parasites in the Arctic
  • Summer 2025, flexible working offered
  • Pay: £12.45/hour, up to 200 hours
  • Deadline: 09.04.25

Adapting to a Changing Environment

  • Populations can adapt to environmental changes through:
    • Dispersal (moving)
    • Adaptation to new conditions
    • No adaptation leading to dire consequences

What Constitutes a Changing Environment?

  • Anthropogenic changes: habitat destruction, biodiversity loss, pollution, climate change, over-exploitation
  • Natural changes: Fire, storms, ecological disturbance, climate fluctuations, succession

Dispersal

  • Migration to track favored environment
  • Example: Migratory birds using flyways
  • Animal migration: long-distance movement, usually seasonal
  • Example: Monarch butterflies migrate up to 4,000 km

Adaptation

  • Hibernation: coping with cold and reduced food availability
  • Example: Syrian hamster using 80% of stored energy during hibernation
  • Hibernation patterns can be influenced by bacterial growth; waking up may help prevent infections
  • Cryopreservation: Wood frogs can survive freezing

Consequences of No Adaptation

  • Bats and white-nose syndrome: Emerged in 2006, causing millions of bat deaths

Anthropogenic Impact

  • Over-exploitation, habitat alteration, and global climate change are sustained pressures
  • Rate and extent of change may exceed adaptive capacities

Over-Exploitation

  • Harvesting species faster than natural recovery rates
  • Example: American Bison skull pile (1870s)
  • Example: Fishing trawlers (2013)

Global Climate Change

  • Temperature anomaly: Increase in global mean temperatures based on land and ocean data
  • Species shifting ranges: Moving away from the equator and to higher elevations
    • Latitude shifts: 16.9 kilometers per decade
    • Elevation shifts: 11.0 meters per decade
  • Climate change is too fast for some species, or there is nowhere to go

Coral Reef Bleaching

  • High water temperatures cause corals to expel algae, losing color and energy
  • Corals can adapt to heat, with heat-tolerant corals gaining a reproductive advantage

Extinction

  • 6th Mass Extinction (Defaunation)
  • Losing ~11,000 to 58,000 species annually
  • 16 to 33% of vertebrates are globally threatened
  • Insect annihilation: Over 40% of insect species threatened with extinction due to habitat loss

Tragedy of the Commons

  • Depletion of a limited resource due to selfish individual actions
  • Example: Atlantic cod over-exploitation led to a fishing ban and ecosystem restructuring
  • Example: Passenger pigeon extinction due to hunting and social system breakdown (Allee effect)

Shifting Baseline Syndrome

  • Each generation perceives current conditions as “normal”
  • Ecosystem shifts and changes in species traits (e.g., fish length)

Adaptation Summary

  • Dispersal, adaptation, or extinction