For Teachers

Letter to Educators



Why Study Rare Breeds?

ALBC Conservation Priorty List


~ K-2 Overview


~ 3-5 Overview



Farm Visits

Third Grade Unit

Leading Question: Rare Breeds: Who are they? Why are they important?


The leading question for this unit is: Who are they? Why are they important? Through the slideshow and accompanying activities the unit address these global questions. Inquiries focus on interrelationships. Students ask: What do they look like, what do they do, what do they eat? Who depends on them? What do they depend on?

In Science, third graders generally learn about plants and animals, relationships between organisms, and animal characteristics and behavior. In Social Studies, they study communities. Through this unit, student realize that farm animals are important. People and animals have lived together for thousands of years. Animals provide people with food, fiber, and services, including companionship. As students look at these relationships, they gain understanding of patterns of interdependence. They notice dependence of animals on plants, of people on animals and plants, and of people on other people.

We depend on them; they depend on us. The interrelationships become apparent. Grounded in the history of animal domestication, the third grade unit explores how both humans and environmental factors have influenced the development of rare breeds. Students become familiar with the incredible diversity and variety that exists in farm animals, and come to appreciate the benefits of genetic diversity.

Key Concepts

• The characteristics of organisms • Regulation and behavior

- define animals as living things that can move around, get food for fuel, and reproduce. - define plants as living things that make their own food, reproduce, but cannot move around.

• Food chains • Interdependence

- name products from a variety of species of farm animals - understand how machines have replaced animals in doing farm work, and the costs and benefits involved.

• Communities • Classifying animals/living things



Throughout human history, wild species have been domesticated and utilized for products and services. Humans provide animals with basic needs (food, shelter, water), and in turn get their needs met (food, clothing, protection, transportation). The history of domestication is a fascinating study in the interdependence of humans, plants, animals and local ecosystems. The history of domestication reminds us how we are a part of nature.

Domesticated animals are those which share the habitat of human beings and whose care and reproduction is under the control of humans. The term "domesticated" is applied to species, not to individual wild animals which have been tamed. (These would be called "tame wild animals. ")

Domestication of animals was a product of nature, not simply a human invention. Except for the domestication of dogs (approximately 12,000–10,000 years ago), domestication of animals generally followed the domestication and cultivation of plants, beginning about 9,500 years ago. Domestication occurred in many parts of the world, though particularly in the Middle East, Asia, Mesoamerica, and Peru.


As agriculture developed, the ancestors of domesticated animals – goats, sheep, cattle, horses, and others – began to share a habitat with people. These were not the first interspecies relations. Many cooperative relationships exist in nature, such as those between finches and wasps, ants and trees, cattle and cattle egrets.

In much the same way, domestic animals and people have been interdependent for thousands of years A habitat near people provided animals protection from predators and often shelter as well. Domesticated animals or animals in captivity availed themselves of the wild food available in the surrounding habitat. As people settled down and became non-nomadic, they began growing grain and grasses, and the domestic animals came to rely on people for food, as well as on local browse and graze. People also gained advantages, such as access to meat and other animal products and services.

The interdependence of people, plants and animals is very apparent when we see how people rely on plants to feed their animals so that they can in turn eat meat or utilize the animals' products and services such as for milk and wool. Besides the products and services provided by animals, people also keep domestic animals for companionship, healing, pleasure, religious ceremonies and recreation, such as horse racing.



Over the centuries, different species of domestic animals have been utilized for different jobs. In recent history, machines have replaced animals. In some ways, machines make farm work easier and faster. On the other hand, animals use renewable resources rather than non-renewable fossil fuels to do some of the same tasks. The farmer uses a machine to do one job efficiently. Yet, in a small scale farming operation, animals can do that job (such as weeding) without the farmer even being there, and in addition to this service also provide the farmer with food and fiber.

There are costs and benefits to replacing animal labor with machines. Without a job or service the animals are not valued. Without value, they are not given a home, and without a home, they become threatened with extinction.

How are we dependent on animals?

Different species have been utilized for different jobs. The following is a list of domestic species around the world and the jobs and services they provide. Also listed are the machines or other technologies that have replaced the work once performed by these animals. Without a job or service the animals are not valued. Without value, they are not given a home, and without a home, they become threatened with extinction.

Animal Products and Services:

The following is a list of domestic species in the United States and around the world with the jobs and services they provide. Also listed are the machines or other technologies that have replaced the work once performed by these animals. For a quick review, see: AnJobsRef.pdf for a lisiting by job or service and AnJobs.pdf for a listing by animal and the blank form for students.

Dogs: watching and guarding animals, herding, providing seeing eye service, hunting, retrieving, tracking, racing, companionship. Security systems replace watch dogs. Dogs are still valued for their companionship.

Cats: controlling rats and mice, companionship. Poisons replace cats hunting.

Mules, Oxen: draft power. Tractors replace the draft animals.

Horses, Elephants, Camels: riding. Vehicles replace the draft animals. Draft horse breeds are rare, while pleasure riding and competition breeds of horses are abundant since they provide a desired service.

Chickens, Ducks and Geese: Pest control. Pesticides replace poultry.

Angora Rabbits, Sheep and Goats: provide wool and fiber. Human made (synthetic) fibers replace wool, cashmere, mohair, silk and other fibers

Sheep, Goats and other mammals: provide horn and bone. Plastics replace these.

Poultry and Pigs: recycle food waste. Landfills replace them.

Many farm animals eat weeds. Herbicides replace the animals and poison the weeds. Mowers replace grazing of all species. Goats, Pigs, Poultry, and predatory insects eat plant pests. Pesticides replace them by poisoning the bugs. Domestic species provide a ready source of manure. Synthetic fertilizers replace manure.

Other animal services that have been replaced include:

Reindeer: draft power, milk, meat, hides for leather. Falcons: hunting. Water buffalo: milk, draft power, meat. Yak: milk (especially for butter), hair for ropes, draft power, meat. Camel: riding, carrying packs, meat, milk. Pigeons: carrying messages. Silkworm: fiber (silk).

Each of these replacements has repercussions in the local ecosystem. While we will not detail the systemic issues involved in every example given above, here is one:

Domestic species provide a ready source of manure. When synthetic fertilizers replace manure, the whole system gets stressed by a multitude of factors. Manure is not recycled as it could be (allowed to decompose and worked into the soil over time). When manure piles accumulate they become a threat to the local watershed. Additional synthetic fertilizer imported into the system from somewhere else throws the carbon load further out of balance. When synthetic fertilizer is added to the top layer of the soil, it becomes vulnerable to rain. Loose fertilizer (accumulated from too many animals in one place, or sitting in the topsoil) runs-off easily, travels to nearby creeks and streams, and adds to non-point source pollution of surface waters. Fertilizer in the water leads to algal blooms. The plants use up the dissolved oxygen, this causes death to aquatic creatures, water bugs and small fish, and a disruption of the food web.

We all live downstream. We are all connected. We are interdependent.


Food Chains and Food Webs

The relationship among animals and plants in a biological community is called a food chain or food web. Food chains generally begin with producers (usually green plants), include a variety of consumers (herbivores, carnivores, and omnivores), and end with earthworms and microorganisms (such as bacteria, fungi, nematodes, and yeast) that decompose organic material above and below the ground. Decomposition of plants, animals, and manure by these microorganisms serves to release nitrogen and the other elements into forms that can be used by growing plants.

Each food chain can have many branches and quickly become a food web. For example, when producers (green plants) die, they are consumed directly by decomposers (such as fungi). Alternatively, producers may be eaten by primary consumers (usually herbivores), which in turn may then be eaten by secondary consumers such as carnivores or omnivores. When carnivores or omnivores die, they are consumed by scavengers and microorganisms. All members in a community contribute to a food chain, and a stable food chain allows all members to thrive.

In a grassland ecosystem, grasses and other plants must be grazed for the plants to remain healthy. For this reason, grazing animals are an essential element of healthy grasslands. Grazing stimulates root growth, which provides organic matter to the soil. The manure of grazing animals is good fertilizer for grasslands as well. If grazing animals are not present, then mowing is necessary to accomplish some of the same purposes.


Navigating the Unit

3rd - 5 E Summary
3rd - Engage
3rd - Explore
3rd - Explain
3rd - Expand
3rd - Evaluate
3rd - Supplement

Noah's Ark Today is property of the American Livestock Breeds Conservancy.
Copyright 2006.

American Livestock Breeds Conservancy, PO Box 477, Pittsboro, NC 27312