Explore how organisms compete for limited resources and use structural features, colouration and behaviour to live successfully in their habitats.
BiologySS 330 minutesInteractive quiz
🌿🦎🍃
Key idea
What is adaptation?
Adaptation: the possession of special features that improve an organism’s chances of surviving in its environment.
Adaptations may involve body structures, colour patterns or behaviour. They help organisms obtain food, avoid predators, attract mates, conserve water, regulate temperature and survive harsh conditions.
Learning objectives
By the end of this lesson, you should be able to:
Define competition and adaptation.
Differentiate intraspecies and interspecies competition.
State the three modes of adaptation.
Give examples of structural adaptation.
Classify adaptive colouration.
Explain examples of behavioural adaptation.
Before adaptation
Competition and survival
Competition is the struggle among living organisms for limited resources. Plants may compete for light, space, nutrients and water, while animals may compete for food, space or mates.
🌽
Intraspecies competition
Competition between organisms of the same species—for example, many maize seedlings growing in a small area.
🌶️
Interspecies competition
Competition between different species—for example, maize and pepper seedlings sharing a small area.
Connection to succession: competition can lead to the gradual replacement of earlier inhabitants of a habitat by organisms better suited to the changing conditions.
Three modes
How organisms adapt
🦅
Structural adaptation
Special body structures or modifications that improve survival.
🎨
Adaptive colouration
Colours or patterns used to hide, warn, attract or imitate.
🐾
Behavioural adaptation
Actions or habits that help an organism survive and reproduce.
Structural adaptation
Special body features for survival
👅
Obtaining food
A toad’s long sticky tongue catches prey; birds may have strong curved claws; insects have modified mouthparts.
🛡️
Escape and defence
Spines, shells, scales, stings and venom protect organisms or discourage predators.
🦚
Attracting mates
Bright colours in male agama lizards, peacocks and domestic fowls help attract mates.
🌡️
Temperature regulation
Fat layers, sweat glands, feathers and subcutaneous fat help control heat loss.
💧
Water conservation
Needle-like leaves, thick bark, waxy cuticles, scales and exoskeletons reduce water loss.
🌺
Pollination support
Bright flowers and specialised plant structures attract insects and improve reproduction.
Adaptive colouration
When colour becomes a survival tool
🦎
Concealing colouration
Camouflage helps organisms blend with their background. Examples include green grasshoppers, green snakes and chameleons.
Behavioural adaptation
Actions that improve survival
PredationLions chase prey at speed; spiders spin webs to trap food.
Escape and defenceAntelopes run quickly, beetles release offensive odours and toads puff themselves up.
Harsh-weather survivalAestivation, hibernation and migration help organisms survive heat, cold or food scarcity.
Plant behaviourSome plants shed leaves in the dry season; seeds remain dormant; shoots grow toward light.
Group behaviourElephants, zebras, birds, fish, bees and termites gain safety or efficiency by living or moving in groups.
Care and communicationOrganisms communicate, attract mates, protect young and coordinate feeding.
Mother-tongue reinforcement
Review the key idea
English summary
Adaptation is a special feature or behaviour that helps an organism survive in its environment. Adaptations may be structural, based on colouration, or behavioural.
Question 1 of 5
Assignment
Apply your understanding
Give two examples each of structural adaptations for obtaining food, attracting mates and conserving water.
Use aestivation, hibernation and migration to explain behavioural adaptation.
Observe one plant and one animal in your environment. Identify an adaptation and explain how it supports survival.
