Web of Life

Strand 1: Inquiry Process

Concept 1: Observations, Questions, and Hypotheses

• PO1. Compare common objects using multiple senses.
• PO2. Ask questions based on experiences with objects, organisms and events in the environment. (see M01-S2C1-01)
• PO3. Predict results of an investigation based on life, physical, and Earth and space sciences (e.g., animal life cycles, physical properties, Earth materials).

Concept 3: Analysis and Conclusions

• PO1. Organize (e.g., compare, classify, and sequence) objects, organisms, and events according to various characteristics. (see M01-S4C4-01)
• PO2. Compare the results of the investigation to predictions made prior to the investigation.

Concept 4: Communication

• PO1. Communicate the results of an investigation using pictures, graphs, models and/or words. (see M01-S2C1-02 and W01-S3C3-02)

Strand 4: Life Science

Concept 1: Characteristics of Organisms

• PO1. Identify the following as characteristics of living things: growth and development, reproduction, response to stimulus.
• PO2. Compare the following observable features of living things: movement – legs, wings, protection – skin, feathers, tree bark, respiration – lungs, gills, support – plant stems, tree trunks.
• PO3. Identify observable similarities and differences (e.g., number of legs, body coverings, size) between/among different groups of animals.

Concept 2: Life Cycles

• PO2. Identify similarities and differences between animals and their parents. (see 1CH-F4)

Concept 3: Organisms and Environments

• PO1. Identify some plants and animals that exist in the local environment.
• PO2. Compare the habitats (e.g., desert, forest, prairie, water, underground) in which plants and animals live.
• PO3. Describe how plants and animals within a habitat are dependent on each other.

Strand 5: Physical Science

Concept 1: Properties of Objects and Materials

• PO1. Classify objects by the following observable properties: shape, texture, size, color weight.

Strand 6: Earth and Space Science

Concept 3: Changes in the Earth and Sky

• PO1. Analyze how the weather affects daily activities.

Strand 1: Inquiry Process

Concept 1: Observations, Questions, and Hypotheses

• PO1. Formulate relevant questions about the properties of objects, organisms, and events in the environment. (see M02-S2C1-01)
• PO2. Predict the results of an investigation (e.g., in animal life cycles, phases of matter, the water cycle).

Concept 4: Communication

• PO1. Communicate the results and conclusions of an investigation (e.g., verbal, drawn, or written) (see M02-S2C1-02 and W02-S3C2-01)

Strand 2: History and Nature of Science

Concept 2: Nature of Scientific Knowledge

• PO1. Identify components of familiar systems (e.g., organs of the digestive system, bicycle).
• PO2. Identify the following characteristics of a system: consists of multiple parts or subsystems, parts work interdependently.

Strand 4: Life Science

Concept 2: Life Cycles

• PO1. Describe the life cycles of various mammals.
• PO2. Compare the life cycles of various organisms.

Strand 1: Inquiry Process

Concept 1: Observations, Questions, and Hypotheses

• PO1. Formulate relevant questions about the properties of objects, organisms, and events in the environment using observations and prior knowledge. (see M03-S2C1-01)
• PO2. Predict the results of an investigation based on observed patterns, not random guessing.

Strand 4: Life Science

Concept 1: Characteristics of Organisms

• PO1. Describe the function of the following plant structures: roots – absorb nutrients, stems – provide support, leaves – synthesize food, flowers – attract pollinators and produce seeds for reproduction.

Concept 2: Life Cycles

• PO1. Compare life cycles of various plants (e.g., conifers, flowering plants, ferns).
• PO2. Explain how growth, death, and decay are part of the plant life cycle.

Concept 3: Organisms and Environments

• PO1. Identify the living and nonliving components of an ecosystem.
• PO3. Explain the interrelationships among plants and animals in different environments: producers – plants, consumers – animals, decomposers – fungi, insects, bacteria.
• PO4. Describe how plants and animals cause change in their environment.
• PO5. Describe how environmental factors (e.g., soil composition, range of temperature, quantity and quality of light or water) in the ecosystem may affect a member organism’s ability to grow, reproduce, and thrive.

Concept 4: Diversity, Adaptation, and Behavior

• PO1. Identify adaptations of plants and animals that allow them to live in specific environments.
• PO2. Describe ways that species adapt when introduced into new environments.
• PO3. Cite examples of how a species’ inability to adapt to changing conditions in the ecosystem led to the extinction of that species.

Strand 1: Inquiry Process

Concept 4: Communication

• PO1. Communicate verbally or in writing the results of an inquiry. (see W04-S3C3-01)

Strand 3: Science in Personal and Social Perspectives

Concept 1: Changes in Environments

• PO1. Describe how natural events and human activities have positive and negative impacts on environments
  (e.g., fire, floods, pollution, dams).
• PO2. Evaluate the consequences of environmental occurrences that happen either rapidly (e.g., fire, flood, tornado) or over a long period of time (e.g., drought, melting ice caps, the greenhouse effect, erosion).

Strand 4: Life Science

Concept 1: Characteristics of Organisms

• PO1. Compare structures in plants (e.g., roots, stems, leaves, flowers) and animals (e.g., muscles, bones, nerves) that serve
  different functions in growth and survival.

Concept 3: Organisms and Environments

• PO1. Describe ways various resources (e.g., air, water, plants, animals, soil) are utilized to meet the needs of a population.

Concept 4: Diversity, Adaptation, and Behavior

• PO1. Recognize that successful characteristics of populations are inherited traits that are favorable in a particular environment.
• PO2. Give examples of adaptations that allow plants and animals to survive: camouflage – horned lizards, coyotes, mimicry – Monarch and Viceroy butterflies, physical – cactus spines, mutualism – species of acacia that harbor ants, which repel other harmful insects.

The Web of Life activity is designed to introduce and explain the “balance of nature”. Students will learn how plants and animals are constantly interacting with each other and if these interactions and/or relationships are in balance, the natural world remains healthy. It is stressed that we are also part of the web and have a responsibility to take care of it so that we and all other living creatures can continue to enjoy a healthy environment. This activity is usually taught to older students although the material can be modified for younger ones as well. The students will experience many hands-on activities to facilitate this understanding.

The Web of Life is introduced to the students with an explanation on the transfer of energy. All living things need energy from the sun to survive. Plants and some other organisms are able to produce their own energy using photosynthesis to change the sun’s energy into chemical energy (food) they can use. These plants and organisms are called producers, ex: grass, plants, trees and cacti. Animals are not able to make their own energy through photosynthesis, but instead rely on plants or other animals to obtain energy. They are called consumers. Animals that eat producers (plants) directly are called herbivores. Carnivores and omnivores are discussed and how each contributes to the balance of nature.

The activity contains many animal skulls, skins, foot impressions and scat. All of the animals represented are found in Sabino Canyon. Skulls, foot and leg samples, scat and skins help explain how the structure of each animal enables it to survive. How do they use their various body parts for defense, foraging, predation, digging, padding, protection, hunting, etc.?

The physical representation of a web enables the students to understand how each strand supports the entire ecological community. They learn that a problem with one part of the web affects the entire community.

Energy Transfer

The sun provides energy to the earth. Plants, producers, use sunlight in a process called photosynthesis to make their own food. Animals, consumers, receive energy by eating plants. Animals that eat or consume plants are herbivores. Animals that eat or consume both plants and animals are omnivores. Animals that eat other animals are carnivores.
Scavengers are animals that feed on dead plants and animals. They help to clean up the environment. Decomposers turn dead matter into material that can be used by producers (plants).

Predator-Prey

Predators are animals that hunt and eat other animals and prey are animals that are hunted and eaten by other animals.

• Predators often have good vision, a keen sense of smell and excellent hearing. Owls, hawks, mountain lions and bobcats have front facing eyes and binocular vision that helps them better judge distance. “Eyes in front…I can hunt”. Their sharp claws or talons help them grip prey. They use sharp, curved beaks or canine teeth to “scissor-cut” food. Their forward-facing ears increase their hearing. Owls have dish-shaped faces that act as sound collectors.
• Prey have large eyes on the sides of their head to give them wider views of surroundings. This enables them to better detect predators in many directions without turning their head. “Eyes on side…I will hide”. Their ears are often large and swivel to detect sounds better, ex: rabbit, squirrel, and deer. Prey often use camouflage to disguise themselves. Their colors of tans and grays blend with grasses and shadows making it more difficult to be seen.

Balance of Nature is the interdependency between plants and animals form the strands of the Web of Life with a tendency toward balance of producer-consumer, predator-prey relationships. Drought years reduce plant growth, which then reduces rabbit and deer populations, which reduce bobcat, mountain lion and coyote populations. Removing predators will increase rabbit and deer populations. Over population of herbivores can lead to their starvation.

Nature, if undisturbed, will always move towards a balance of predator and prey as seasons and plant growth permit. Nature’s recovery from natural causes such as fire, flood, or hurricane, begin immediately from the simplest organism to the final complete ecosystem.

Sabino Canyon, when automobiles were allowed, had oil, anti-freeze and gas drippings. Broken glass in streams and picnic areas caused injury. Native wildlife was rarely seen. Human-created pollution needs cleanup and remediation for nature to return to a balance.