10.7 Adaptations Flashcards
Adaptations
Characteristics that increase an organisms chances of survival in their environment.
3 types:
- anatomical (physical external/internal features)
- behavioural (way they act)
- physiological (processes internally occurring)
Anatomical
- Body covering - fur to stay warm, scales, thick waxy layers to prevent water loss in plants, shells for protection.
- camouflage - harder for predators to spot them
- teeth - molars to chew grass, canines to chew meat
- mimicry - copying appearance/sounds to fool predators to think they’re dangerous.
E.g. marram grass - to live in dry conditions:
stomata in pits to prevent water loss
hairs on inside of leaves to trap moist air and decrease diffusion gradient.
Behavioural
- survival - e.g. possums play dead
- courtship - to attract a mate, scorpions dance
- seasonal - to survive in seasonal changes
- migration
- hibernation
Behavioural splits into 2 types:
innate ( instinctual) inherited through genes
learned behaviour from observation
Physiological
- poison production (many reptiles produce venom for prey and predators)
- antibiotic production (some bacteria produce antibiotics to kill other species)
- water holding (e.g. water-holding frog can store H2O in its body when in dry conditions)
Others include blinking, reflexes and temperature regulation.
Anatomical adaptations and evidence for COVERGENT EVOLUTION
Analogous structures - structures with same functions but different genetic origins.
CONVERGENT EVOLUTION - when unrelated species begin to share similar traits; evolved from being in similar environments or SELECTION PRESSURES.
Marsupials start in the uterus then leave and continue to develop in the marsupium (e.g. kangaroo pouch).