Adaptation to the environment

• Abiotic


  • Non living
  • Air
  • Light
  • Soil minerals
  • Climate
• Habitat


  Description of the geographical location, type of ecosystem and physical location within an ecosystem
• Species


  Group of organisms that can interbreed and produce fertile viable offspring
• Community


  Group of populations living and interacting with each other
• Population


  Same species in the same area and time
• Climograph


  Graphical model that shows the relationship between temperature, precipitation and ecosystem type
• Tropical rainforest


  • High rainfall, temperature and light intensity
  • No cold season
  • Thin, nutrient poor soil
• Tundra


  • Low temperature
  • Short summer
  • Low to medium precipitation as snow
  • Low light
• Temperate forest


  • Moderate temperatures with warm summers and cold winters
  • Medium to high rain
  • Moderate light
• Grassland


  • Medium to high temperature in summer
  • Cold winter
  • Moderate rain
  • Dry season
  • Medium to high light
• Desert


  • Hot day, cold night
  • Low rainfall
  • Droughts
  • Limited soil development
• Taiga


  • Low temperatures
  • Short summers
  • Medium to high precipitation
  • Low to medium light
• Saguaro cactus


  • Wide roots
  • Tap roots reach deep subsoil
  • Wide stem for water storage tissue
  • Pleated stems shrink in droughts and swell after rain
  • Vertical stems reduce overheating
  • Thick waxy cuticle
  • No leaves, spines reduce surface area
  • CAM metabolism
• Fennec foxes


  • Nocturnal
  • Underground den
  • Thick hair for insulation
  • Hair covers feet pads
  • Pale coat reflects sun
  • Large ears radiate heat
  • Increased ventilation rate
• Camels


  • Concentrated urine for water conservation
  • Fat storage in humps
  • Large surface area to volume ratio
  • High temperature tolerance
  • Long legs
  • Long nasal passages trap and absorb water
  • Broad feet
• Dipterocarp trees


  • Tall, increased photosynthesis
  • Fast growth to reach canopy
  • Buttress roots grow overground to prevent toppling
  • Large leaves maximize light absorption
  • Lots of fruit increase reproductive success
• Sumatran orangutans


  • Long arms and grasping feet for swinging on branches
  • Opposable fingers and toes to grasp branches
  • Color vision to recognize fruits and predators
  • Brown/red color for camouflage
  • Intelligent, uses tools to obtain food
  • Strong jaws and teeth to eat unripe fruit
• Marram grass


  • Xerophyte
  • Thick waxy cuticle prevents water loss
  • Leaves roll up during droughts to create a humid chamber and reduce wind exposure
  • Indented stomata reduce transpiration
  • Rhizomes for stability and reaching deep water
  • Accumulation of carbohydrates in root + leaf cells increases osmosis potential
• Mangrove trees


  • Pneumatophores grow up to access oxygen
  • Cable roots grow into the ground for stability
  • Stilt roots act as an anchor for stability
  • Buoyant seeds carried by ocean currents, dispersed to fertile soil
  • Salt glands in leaves remove excess soil
• Shelford's law of tolerance

  • Organisms have optimal survival rates for abiotic factors
  • As organisms move from areas with optimal conditions, survival decreases
  • Three zones: Optimum (maximum survival), Zone of stress (decreases survival), Zone of intolerance (no survival)
  • Variables: pH, temperature, light, water, salinity
• Transect


  • Arbitrary line through a habitat to systematically sample the community
  • Line transect: tape laid out in the direction of an environmental gradient, all organisms touching the tape are recorded
  • Belt transect: all organisms within a band are sampled along an environmental gradient
• Factors affecting growth of coral

  • Water clarity: turbidity prevents light penetration for photosynthetic zooxanthellae
  • Water depth less than 50 meters so light penetrates
  • Low temperature kills coral, high temperature releases zooxanthellae
  • 7.8 pH to allow deposition of calcium carbonate
  • Salinity, to avoid osmotic problems
• Convergent evolution


  • Independent evolution of similar features in species
  • Deserts in America and Africa have many species with similar characteristics
  • Cacti and Euphorbia are not closely related