Teacher background information

This elaboration provides students with the opportunity to investigate the long-held scientific understanding Aboriginal and Torres Strait Islander Peoples have of the life cycles of species within their Country/Place. For millennia Aboriginal and Torres Strait Islander Peoples have used knowledge and understanding of the life cycles of organisms to acquire and utilise resources from the environment. These resources are important for the construction of tools, weapons, implements and shelters, to manufacture clothing and to procure food and medicines. An understanding of the life cycles of organisms informs the appropriate time for the careful, considered harvest of flora and fauna species to protect the sustainability of the organism and provide continued access to the resource. Students will learn how the intricate understanding of the life cycles of organisms has long informed Aboriginal and Torres Strait Islander Peoples’ decisions regarding when to acquire and utilise resources.

Phenology is the study of plant and animal life cycle events and how these are influenced by changes in season, climate and habitat. For millennia, Aboriginal and Torres Strait Islander Peoples have studied patterns in the environment and have developed an intimate understanding of these interconnected factors. Aboriginal and Torres Strait Islander Peoples’ understanding of seasons is quite different from the European perspective which divides the calendar year into four distinct seasons based on the Gregorian calendar months. Aboriginal and Torres Strait Islander Peoples distinguish seasons based on many factors including, but not limited to, climatic conditions, and plant and animal life cycle indicators, and events.

Australia’s First Nations Peoples’ seasonal calendars vary due to the diversity of environments and climatic conditions across the Australian continent. For example, the seasonal calendar of the Miriwoong Peoples, whose Country encompasses the east Kimberley region of Western Australia and extends into the Northern Territory, comprises three seasons, whereas the seasonal calendar of the D'harawal Peoples of the region north of Sydney encompasses six seasons. Aboriginal and Torres Strait Islander Peoples hold a wealth of knowledge about the life cycles of species and the intrinsic relationship with seasonal variation can be seen in such seasonal calendars. Documenting the calendars has informed the scientific understanding of the relationships between Aboriginal and Torres Strait Islander Peoples and the seasonal cycles of resource availability.

The coastal floodplain Country in the Kakadu region of the Northern Territory encompasses a vast wetland area that has long been managed and maintained by the Bininj and Mungguy Peoples to support the vast diversity of wildlife in the region. Magpie geese breed in the wet season; this timing coincides with wetland flooding which supplies abundant food resources for the birds. Aboriginal Peoples of these regions understand the life cycle of magpie geese and the behaviour associated with their breeding patterns. In Gudjewg (monsoon season, December–March on the Gregorian calendar), magpie geese flock to the Kakadu region where heat and humidity provide a plentiful supply of rushes and grasses for the magpie geese to build nests. For millennia, the land has been managed by burning intrusive plants to maintain a plentiful supply of food resources that ensure the return of the birds for breeding every monsoon season. The magpie geese begin laying about two months after nest building and clutch size varies from a single egg up to 14 eggs per breeding cycle. Aboriginal Peoples’ knowledge of the life cycle informs the sustainable harvest of eggs that provides a staple food source through the wet season. Goslings hatch after approximately 25 days of incubation and spend a day in the nest before being led through the swamp by their parents. The goslings are able to fly after about 10 weeks but remain with their parents until the following breeding season. Hunting the magpie geese begins in wurrgeng (the cold time; June–August on the Gregorian calendar) when the magpie geese are fat and heavy after abundant food, and continues into gurrung (the hot, dry season; mid-August–October on the Gregorian calendar). Aboriginal Peoples’ intricate understanding of the life cycle of the magpie goose and the interrelated seasonal factors has informed sustainable harvesting of eggs and adult birds for millennia. Understanding and utilising the life cycle of the magpie goose facilitates hunting for eggs and birds and ensures the fulfilment of cultural obligations in the ongoing management of Country.

Peoples of the Islands in the Torres Strait also eat birds, in particular the Torresian imperial pigeon called gainau in the Kalaw Lagaw Ya Language of the western Torres Strait Islander Peoples and daumer in the Meriam Mir language of the eastern Torres Strait Islander Peoples. At the end of the monsoon season, the pigeons migrate from New Guinea and nest in the mangrove areas of the Islands. The pigeon lays one or two eggs that are incubated for about 27 days by both parents and the adult birds flock daily to inland areas to feed on the wild nutmeg trees. Many Torres Strait Islander Peoples understand and utilise the behavioural patterns of the pigeons associated with their life cycles and hunt the birds as they migrate in predictable patterns.

Grass trees (Xanthorrhoea spp.) have long been a culturally important species for many Aboriginal Peoples across Australia and knowledge of the life cycle of these plants, and when components can be harvested for use, is well understood. The plant provides material for many purposes, including resin, food, nectar, fibre and wood to construct implements and weapons. Grass trees are endemic to Australia and are found across all states and territories, although some species are restricted to particular regions. Xanthorrhoea spp. are monocots, flowering plants that have only one embryonic leaf in their seeds. The plant begins as a crown of rigid grass with a stem root that grows slowly underneath. Grass trees may take several years to flower. Flowers form in a spiral arrangement on a spike that protrudes from the centre of the leaves that skirt the trunk of the plant. The first flowers on the spike to emerge have been recorded as indicators of direction as they always open facing north. The flowers produce a nectar that attracts birds and insects and can also be used to sweeten drinks. Peoples of some Language Groups of Tasmania soak the flowers of the grass tree in fresh water to release the nectar and make a sweet drink. In the southwest of Western Australia, the Noongar Peoples produce a fermented beverage by soaking grass tree (balga) flowers in boat shaped bark vats for several days. The pollinated flowering stem of the grass tree can produce up to 10,000 seeds that can take up to a year to germinate. The Gunditjmara and Wurundjeri Peoples of the Mornington Peninsula region in Victoria grind the seeds into a flour to make bread.

The growth rate of the grass tree is very slow; the plant extends approximately one to two centimetres annually, although the long spike can grow to a length of up to four metres. The growing tip of the stem is edible, although it is rarely consumed as its removal destroys the plant completely, and the opportunity to produce further resources. The dried spike has long been used for many purposes by Aboriginal Peoples. It can be used in the construction of lightweight spears and as a drill stick for starting fire. The Noongar Peoples of south-west Western Australia use the dried flower stems of grass tree (balga) as a torch. Many First Nations Peoples, including the Yirrganydji and Yidinji Peoples of the Cairns region, the Cammeraigal Peoples of the Eora Nation in the region now known as Sydney, and the Peoples of some Language Groups of Tasmania use the dried stem of the grass tree as a drill stick for starting fire. The young, soft leaf bases of the grass tree can be eaten fresh and this has long provided many peoples, including the Woiwurrung Peoples of the Kulin alliance in central south Victoria, with a nutritious food resource. The older leaves become tough and are used by the Wurundjeri Peoples of the Yarra River Valley in Victoria as a tool to cut meat. The Noongar Peoples also use the leaves in the construction of roofs for shelters, as the structure of the leaves directs rainwater along the underside of the fronds, keeping the occupants of the shelter dry. The Woppaburra Peoples of the Keppel Island region in Queensland use the butt of the grass tree to construct educational toys called kamma, named after the Language name of the grass tree. Resin is produced at the leaf base of some species of grass trees. Aboriginal Peoples have collected and used this resin in many different applications: a waterproofing agent on canoes and water-carrying vessels such as coolamons, as an adhesive to fix axe heads onto handles and spear tips on spear shafts, and to repair other implements.

Aboriginal Peoples across Australia understand the complex life cycle of the grass tree and utilise components of the plant through the various life cycle stages. For millennia the grass tree has provided materials for many important purposes, and Aboriginal Peoples’ management of the environment that supports and sustains the growth of grass trees reflects a deep understanding of the life cycle of the organism and ensures that the plant continues to yield resources.

The life cycle of insects, such as moths, is also well understood by Aboriginal Peoples and important food resources have long been harvested at identified stages of the insect life cycle. There are four main stages in the life cycle of moths – egg, larva, pupa and adult. During the first stage, the embryonic stage, the embryo develops inside an egg. The embryo hatches into a larva, commonly known as a caterpillar. The larval stage of a particular large wood moth, known to the Adnyamathanha Peoples of the Flinders Ranges region in South Australia as witjuri, bores into the wood of Acacia to feed on plant sap. Sawdust that accumulates on the ground as the larvae bore into the plant provides evidence of their presence. The Adnyamathanha Peoples harvest the larvae as a food source which is rich in protein.

Peoples of some Language Groups of Tasmania harvest and eat the larval stage of a moth species that bores into Banksia spp., and in parts of Queensland Aboriginal Peoples harvest, and lightly roast or eat raw, the larvae of moths found in blue gum saplings or at the base of grass trees. When larva is ready to pupate, it spins a protective cocoon where metamorphosis takes place. The time from pupation to the emergence of the adult moth from the cocoon can take up to three weeks. Caterpillars of a particular species in Victoria form a procession in large numbers along the stems of gum trees to find a place to rest and pupate. The Gunditjmara Peoples of western Victoria have an intricate understanding of the life cycle of these insects and dig the pupal form of the moth from the foot of gum trees in winter to roast in the ashes of a fire as a source of food. Specific adult moth species have immense cultural significance to Aboriginal Peoples. The aestivation of the bogong moth in the cool caves of the Snowy Mountains on the lands of the Ngarigo Peoples in southern New South Wales has long been an occasion for Aboriginal Peoples in the region to unite for a feast. The moths, an extremely nutritious food source with a high fat content, are harvested with smoke and nets crafted specifically for the purpose. The moths are cooked gently on the edge of a fire and the nutrient rich body is separated from wings and heads before consumption. Aboriginal Peoples’ knowledge of the life stages of moth species in Australia has long informed the suitable times for harvesting particular species to benefit from their nutritious properties.

For millennia Aboriginal and Torres Strait Islander Peoples have harvested resources from the natural environment to construct tools, weapons and other implements, manufacture clothing and shelter, and to procure food, drink and medicines. This elaboration provides students with the opportunity to investigate the understanding Aboriginal and Torres Strait Islander Peoples have of the life cycles of species and how this knowledge is used to inform the utilisation of plants and animals. Students will learn how the intricate knowledge of the life cycles of organisms has long informed, and continues to inform, how Aboriginal and Torres Strait Islander Peoples sustainably harvest resources to fulfil these requirements.