Building Science Concepts: Birds

Explore the science concepts that underpin knowledge and understanding about birds and their structure, function and adaptations.

The New Zealand Ministry of Education’s Building Science Concepts (BSC) series presents sets of interlinking concepts that build stage by stage towards overarching science concepts or big ideas. A big idea shows how a fully developed understanding of the concept might look but recognises that such an understanding might not be achieved until New Zealand Curriculum level 7 or 8.

This resource is a partial replication of Building Science Concepts Book 3 Birds: Structure, Function, and Adaptation. The background information on this page, combined with the information in the interactive, covers the science notes provided in the original BSC book. The overarching science concepts (big ideas) and how they may be scaffolded in sequence are illustrated in the interactive below.

Key science ideas – adaptations and structures

An adaptation is any aspect of an organism’s structure, physiology or behaviour that has allowed this species to survive in its present environment. Physical adaptations in birds refer to the different sizes, shapes or colours in structures such as birds’ beaks, feathers, wings or feet. These take many centuries to develop.

Behavioural adaptation refers to individual birds learning how to maximise their survival and reproduction. This happens in a very short timespan – for example, learning how to operate a device to release food.

An organism’s structure refers to some part or a combination of parts of a living thing’s physical make-up. A structure’s function is the way the structure works. All birds have feathers, two legs and a beak – these are the basic structures that define them as birds.

Physical adaptations for flight

Although not all birds can fly, flying is an important characteristic of birds. In order to fly, birds need:

• feathers – birds have strong, lightweight feathers for flying and soft fluffy feathers to keep their flight muscles warm
• strong hearts that beat quickly to transport the energy sources their flight muscles need
• specialised lungs – air flows through the lungs in one direction, supplying more oxygen to support the high energy needs
• lightweight, hollow bones that are strengthened by internal struts
• beaks – pointed shapes help with streamlining for flight and eliminate the need for teeth, which are heavy to carry
• reproductive organs, which can shrink when birds are out of breeding season.

Physical adaptations for swimming and diving

Birds that spend much of their lives in or around water show special feather adaptations. Ducks’ breast feathers form an oily, waterproof cover that is excellent for insulation and buoyancy. Shags or cormorants need their feathers to get waterlogged so they are able to dive more easily to catch fish. Penguin feathers have become a sleek, fine fur for insulation and for streamlined movement underwater.

Adaptations for feeding and habitat

Observing a bird’s beak and feet will indicate their type of preferred food and their habitat/ecological niche. Birds can utilise a range of food resources using their adaptations. Some birds may be herbivores, feeding on plant shoots, berries or nectar. Others are carnivores and hunt other birds or small animals. Omnivores eat a wide variety of small animals, fruits and nectar.

The wider the range of food that birds can tolerate, the greater the range of environments that they can inhabit. Birds that are comfortable living in urban areas usually have a range of foods and are not highly specialised. Gulls and blackbirds tolerate a great range of diets and manage well among humans.

The size and shape of a bird’s feet can provide clues to its food source and its habitat:

• Webbed feet indicate the ability to swim and hunt underwater.
• Large, splayed feet indicate the ability to feed in mud and sand without sinking.
• Sharp talons indicate the ability to catch and hold on to prey.
• Feet with three toes forward and one toe back indicate the ability to keep a firm perch on a moving branch while feeding.

The size and shape of a bird’s beak can provide clues to its food source and its habitat:

• The oystercatcher’s beak can be used to dig up and open shellfish from the sand.
• The fantail’s wide beak with bristles is good for catching insects on the wind.
• The tūī and other nectar feeders have long, slender beaks to dip deep into flowers.
• Most raptors have strong, curved beaks to tear the flesh of their prey.
• Finches have short, sharp beaks for feeding on tiny seeds.

Flight styles and lifestyles

Birds have many different forms of flight. The size and shape of their wings and the detail of the structure of their flight feathers can give an indication of their lifestyle.

The elliptical shape of the wing of the kererū can be easily seen in this image. This shape is perfect for manoeuvring through branches, but ordinary flight is slow and requires flapping. The distinctive wing sound as it beats its way over any sort of distance will be familiar to people who live in Aotearoa.

Adaptations of senses

Most birds’ eyes are set on the sides of their heads, which enables them to see forwards, sideways and backwards at the same time. They also have extremely sharp eyesight. This helps them to find food, keep in touch with each other and avoid enemies. Hawks and eagles have telescopic sight. Their large eyes and sensitive retinas enable them to see prey kilometres away – much further than people can.

Birds’ senses of smell and hearing have become highly developed as bird species have adapted over time to specialised habitats:

• Kiwi, with their nostrils set at the very tip of their beaks, sniff out food as they probe forest leaf litter.
• Albatrosses and petrels in flight can detect the smell of shrimp and fish under the water.
• Thrushes can hear worms moving underground.

Adaptations in New Zealand birds

Aotearoa New Zealand separated from Gondwanaland around 80 million years ago. The article Native bird adaptations explains why native birds evolved unique characteristics.

Alternative conceptions

Students may have alternative understandings of science concepts. These are some involving birds and adaptations:

• Physical adaptations can happen within an individual’s lifetime – particularly if it hasn’t been emphasised that it takes thousands or millions of years for physical adaptations to become distinct within a species.
• Birds have teeth in their beaks to help tear their food apart.
• Birds have eyes in the front of their heads so that they can see ahead.
• Birds digest their food in their mouths.
• Birds can fly due to the air spaces between their cells.

Bringing another lens

New Zealand birds: Māori myth, legend and lore offers information about some of the tohu or signs that different birds signify within te ao Māori. Ngā manu a Tānemahuta provides a brief introduction to Māori knowledge of manu.

Opportunities for citizen science

These projects offer students the opportunity to learn about birds, practise science capabilities and contribute to answering real investigative science questions:

• New Zealand Garden Bird Survey (along with a PLD planning article and the article Te Tatauranga o ngā Manu Māra o Aotearoa – resources for kura – this curates resources to inspire, enlighten and extend learning for tamariki. The resources are in English and te reo Māori.)
• Kea Database
• eBird.

Opportunities for practising the science capabilities

Assessment Resource Banks have a selection of activities that foreground the science capabilities using birds as the context. Some of the activities, alongside the relevant capability, are listed in a downloadable PDF format. Many activities can target multiple capabilities with a different teacher focus or pedagogy. You need to be registered to use Assessment Resource Banks materials.

• ARBs – bird activities and science capabilities