Die Druckversion wird nicht mehr unterstützt und kann Darstellungsfehler aufweisen. Bitte aktualisiere deine Browser-Lesezeichen und verwende stattdessen die Standard-Druckfunktion des Browsers.

Biodiversity and Habitats

Introduction

Welcome to Biodiversity and Habitats. In this course, you will explore the amazing variety of life on Earth and the places where living things survive, grow, feed, reproduce, and interact. You will learn how a tiny patch under a log can be a habitat, how a forest can contain many habitats, and how organisms and non-living parts of the environment form an ecosystem.

Biodiversity means the variety of life. Scientists study biodiversity at different levels, including differences within a species, the variety of species, and the variety of ecosystems. A habitat is the place where an organism lives and finds the conditions and resources it needs.

By the end of the course, you should be able to explain the difference between biodiversity, habitat, ecosystem, and biome; describe how organisms are suited to habitats; build simple food webs; identify causes of habitat change; and suggest realistic ways to protect biodiversity.

Look closely at the satellite image. Forests, savannahs, wetlands, mountains, and other environments can exist near one another. A landscape with many habitat types can support many different communities of living things.

Biodiversity: The Variety of Life

Biodiversity is not only a count of how many kinds of animals you can see. It includes plants, animals, fungi, and microorganisms, as well as the differences among them and the ecosystems they form. A place with high biodiversity may contain many species, but scientists also care about which species are present, how common they are, and how they interact.

Three Levels of Biodiversity

Genetic diversity means inherited differences among individuals of the same species. For example, plants of one species may differ in traits such as size, color, or resistance to disease.

Species diversity means the variety of species in an area. A woodland with many kinds of trees, birds, insects, fungi, and mammals has greater species variety than a place containing only a few species.

Ecosystem diversity means the variety of ecosystems across a region or the planet. Forests, grasslands, wetlands, rivers, deserts, and coral reefs are examples of different ecosystem types.

A rainforest contains many layers and microhabitats. Mosses, ferns, insects, birds, fungi, and other organisms may use different parts of the same forest.

What Is a Habitat?

A habitat is the place where an organism lives. A useful habitat provides the conditions and resources that organism needs. Animals need resources such as food, water, shelter, and enough space. Plants need suitable light, water, air, minerals, temperature, and space for their roots and leaves.

Habitats can be very large, such as an ocean region, or very small, such as the damp space beneath a fallen log. A small, special part of a larger habitat is often called a microhabitat.

As you watch, compare the habitats shown. Ask yourself: What is different about the temperature, water, light, soil, plants, and shelter in each place?

Land and Water Habitats

Land habitats include forests, grasslands, deserts, tundra, mountains, and many human-shaped places such as farms and gardens. Water habitats include ponds, lakes, rivers, wetlands, estuaries, seas, and oceans. Each habitat has its own combination of living and non-living features.

A coral reef is a marine habitat with many hiding places, feeding areas, and surfaces where organisms can live. Reef organisms also interact with water temperature, light, currents, and the chemistry of seawater.

Habitats, Ecosystems, and Biomes

These words are connected, but they do not mean exactly the same thing.

A habitat focuses on the place where a particular organism or population lives. An ecosystem includes a community of living organisms plus non-living parts of the environment, such as water, air, rocks, light, and temperature, and all the interactions among them. One ecosystem can contain many habitats.

A biome is a very large ecological region identified mainly by climate and broad patterns of plant and animal life. Common biome groups include forests, grasslands, deserts, tundra, freshwater environments, and marine environments. Scientists may divide biomes in different ways depending on the question they are studying.

Different fish species are suited to different parts of freshwater and marine environments. Even within water, depth, temperature, current, oxygen, plants, rocks, and seafloor type can create different habitats.

How Living Things Fit Their Habitats

An adaptation is an inherited feature or behavior that helps organisms survive and reproduce in particular conditions. Adaptations develop in populations over many generations; an individual animal does not simply decide to grow a new adaptation because its habitat changes.

A cactus can reduce water loss with a waxy surface and other water-saving features. Many desert animals avoid the hottest part of the day by being active at night. Webbed feet can help some water birds push against water. Camouflage can make an organism harder for predators or prey to notice.

Think like a scientist: When you notice a feature, do not just say that it is "good." Explain what the feature helps the organism do and which part of the habitat makes that useful.

Connections in a Habitat

Living things depend on one another. Green plants and algae are producers because they use light energy to make sugars. Animals and other organisms that eat plants or animals are consumers. Fungi and many microorganisms act as decomposers, breaking down dead material and helping nutrients return to the environment.

A food chain shows one path of feeding relationships. A food web connects many food chains and gives a more realistic picture because most organisms have more than one food source or predator.

Fungi are important parts of many ecosystems. By decomposing dead material, many fungi help recycle nutrients that other organisms can use.

Pollination and Seed Dispersal

Some relationships are not about eating. Pollinators move pollen between flowers, helping many flowering plants reproduce. Animals can also spread seeds in fur, in droppings, or by carrying fruits and seeds. These connections can link the success of plants and animals.

When you see an insect visiting a flower, observe carefully. It may be collecting nectar or pollen, and it may also carry pollen from one flower to another.

Why Biodiversity Matters

Biodiversity supports the processes that make ecosystems work. Healthy ecosystems can provide people and other organisms with benefits such as food, clean water, fertile soils, pollination, places for recreation, and protection from some floods or storms.

Biodiversity can also make ecological communities more able to keep functioning when conditions change, because different organisms may perform different roles. However, a high species count does not automatically mean an ecosystem is healthy. Scientists also look at native species, population sizes, food-web relationships, habitat quality, and changes over time.

When Habitats Change

Habitats change naturally through events such as storms, floods, droughts, fires, erosion, and the growth or death of organisms. Some ecosystems are shaped by repeated natural disturbances. Human activities can also change habitats quickly or strongly.

Major pressures on biodiversity include changes in how land and seas are used, overuse of wild organisms, climate change, pollution, and invasive alien species. Several pressures can act at the same time.

Habitat loss happens when a habitat is destroyed or changed so much that organisms can no longer use it in the same way. Habitat fragmentation happens when one connected habitat is split into smaller, separated patches. Roads, buildings, farms, fences, or other changes can make it harder for some organisms to move between patches.

In this image, a road divides natural areas. Think about which organisms might cross easily, which might struggle, and how a wildlife bridge or other corridor could help.

Climate Change and Habitats

Climate affects temperature, rainfall, seasons, sea ice, ocean conditions, and many other features of habitats. As the climate changes, suitable habitat for some species may shift. Some populations can move, some can adjust within limits, and others may decline if change is too fast or if there is nowhere suitable to go.

Invasive Species

An invasive alien species is a species moved by people outside its natural range that establishes, spreads, and causes harm to biodiversity, ecosystems, or people. Not every non-native species becomes invasive. Scientists look at evidence of spread and harm.

Invasive species can compete with native species, eat them, spread disease, or change habitat conditions. Preventing new introductions is often easier than controlling an invasive species after it has spread widely.

Protecting Biodiversity and Habitats

Conservation means protecting biodiversity and using natural resources in ways that can continue over time. Conservation can include protecting important areas, restoring damaged habitats, reconnecting habitat patches with wildlife corridors, reducing pollution, preventing invasive species, and using forests, fisheries, farms, and other resources more sustainably.

Planting suitable native plants can provide food and shelter for local insects and other wildlife. Leaving some safe natural features, such as leaf litter or dead wood where appropriate, can create microhabitats. Community science projects can help researchers collect observations over large areas.

A biodiversity observation is more useful when you record where, when, and how you observed an organism. Good notes help other people understand your evidence.

A Simple Biodiversity Investigation

Choose a safe outdoor area with an adult or teacher. Mark a small observation zone and spend the same amount of time looking each visit. Record the different kinds of plants, animals, fungi, and signs of life you can observe without disturbing them. Repeat the observation on another day or in a second habitat. Compare the number and kinds of organisms, but remember that seeing fewer organisms does not prove that fewer are present. Weather, time of day, season, and your observation method can affect what you detect.

Reliable Sources for Further Learning

Interactive Tasks

Quiz: Test Your Knowledge

What does biodiversity describe? (The variety of life and its differences) (!Only the number of large animals) (!Only the plants in a forest) (!Only places with warm weather)

What is a habitat? (The place where an organism lives and finds what it needs) (!A list of all species on Earth) (!Only a place built by humans) (!A single feeding relationship)

What is included in an ecosystem? (Living organisms and the non-living environment interacting) (!Only animals that hunt other animals) (!Only the weather in one place) (!Only plants and fungi)

What is an adaptation? (An inherited feature or behavior that helps survival and reproduction) (!A place where an organism sleeps) (!A sudden choice to change body shape) (!A map of a food web)

What does a food web show? (Connected feeding relationships in a community) (!Only one animal and its shelter) (!The temperature of a biome) (!The age of every organism)

What can a pollinator do? (Move pollen between flowers) (!Turn a desert into a forest) (!Break a road into smaller pieces) (!Make seawater fresh)

What is habitat fragmentation? (The splitting of connected habitat into separated patches) (!The natural color variation within one species) (!The recycling of nutrients by fungi) (!The movement of pollen between flowers)

Which statement about non-native species is correct? (Not every non-native species is invasive) (!Every non-native species destroys a habitat) (!Non-native species can never spread) (!Only plants can be non-native)

Which action can improve habitat connectivity? (Creating a wildlife corridor between habitat patches) (!Adding more barriers between patches) (!Removing all native plants) (!Increasing litter in a river)

What is genetic diversity? (Inherited differences among individuals of the same species) (!The number of habitats in one biome) (!The amount of rainfall in a forest) (!The number of food chains in an ecosystem)

Memory Game

Biodiversity	Variety of life at genetic, species, and ecosystem levels
Habitat	Place that provides suitable living conditions and resources
Ecosystem	Community and non-living environment interacting together
Adaptation	Inherited trait or behavior that improves survival or reproduction
Pollinator	Organism that transfers pollen between flowers
Fragmentation	Separation of a connected living area into smaller patches

Drag and Drop

Match the correct terms.	Topic
Warm, wet environment with many layers of vegetation	Rainforest habitat
Dry environment where saving water is important	Desert habitat
Connected feeding relationships among many organisms	Food web
Passage that links separated natural areas	Wildlife corridor
Breaking down dead material and recycling nutrients	Decomposition

...

Crossword Puzzle

Habitat	What word means the place where an organism lives?
Species	What word is used for one kind of organism, such as the gray wolf or an oak?
Ecosystem	What includes living organisms, non-living surroundings, and their interactions?
Adaptation	What inherited feature or behavior can help an organism survive and reproduce?
Pollinator	What kind of organism can carry pollen from flower to flower?
Fragmentation	What word describes the splitting of connected habitat into smaller patches?

LearningApps

Cloze Text

The variety of life on Earth is called

. The place where an organism lives is its

. A community of organisms interacting with non-living surroundings forms an

. A small special part of a larger habitat can be called a

. An inherited feature or behavior that helps survival and reproduction is an

. Green plants are often called

because they use light energy to make sugars. Fungi can act as

by breaking down dead material. A network of connected feeding relationships is a

. Splitting a connected habitat into separate patches is called

. A passage that reconnects habitat patches can be a wildlife

. Protecting biodiversity and using natural resources responsibly are parts of

.

Open-Ended Tasks

Easy

Habitat sketch: Draw a local habitat and label at least five living or non-living features that could affect organisms there.
Microhabitat hunt: With an adult or teacher, find two safe microhabitats, observe them without disturbing them, and write three differences you notice.
Species observation card: Choose one organism you can safely observe, make a picture or photo card, and explain what the habitat seems to provide for it.
Food chain story: Create a short illustrated story that follows energy from the Sun to a producer and then to two consumers.

Standard

Habitat model: Build a model of a forest, grassland, desert, wetland, or aquatic habitat and explain how at least four features meet the needs of organisms.
Biodiversity interview: Interview a gardener, farmer, park worker, family member, or local expert about changes they have noticed in local plants, animals, or habitats, then summarize the evidence and any uncertainties.
Schoolyard habitat map: Map a schoolyard or nearby safe area, mark possible microhabitats, barriers, water sources, and shelter, then suggest one change that could support native species.
Pollinator project: Observe flowers safely, record visiting insects for a fixed time, and present your results in a table or poster without claiming that every visitor is definitely pollinating.

Advanced

Comparative biodiversity survey: Use the same observation method in two habitats, compare the kinds of organisms you detect, and explain how time, weather, and observer skill could affect the result.
Habitat connectivity plan: Study a real or imaginary fragmented habitat, design a corridor or crossing, and justify which organisms it could help and what problems might remain.
Conservation video: Create a two-minute educational video that explains one threat to biodiversity, shows evidence from reliable sources, and proposes realistic actions for a school or community.
Ecosystem change investigation: Research how one habitat is changing because of land use, pollution, climate change, invasive species, or resource use, then make a cause-and-effect diagram that includes at least one possible solution.

Learning Assessment

Habitat evidence explanation: Given two habitat photographs, explain which environmental features could favor different organisms and support each claim with visible evidence.
Food web reasoning: Build a simple food web with at least six organisms, then predict two possible effects if one population becomes much smaller and explain why the effects could spread.
Fragmentation solution: Compare two plans for a road through a natural area and argue which plan better supports habitat connectivity, including one trade-off.
Biodiversity data interpretation: Examine a class dataset from repeated observations, identify a pattern, describe one limitation of the data, and state what extra evidence would make the conclusion stronger.
Adaptation explanation: Choose one organism, connect two of its adaptations to specific habitat conditions, and distinguish an inherited adaptation from a short-term response.
Conservation transfer: Apply what you learned to a new place, such as a city park, farm edge, riverbank, or coast, and propose a small conservation plan that considers both wildlife and human needs.

Evidence of Learning

Knowledge: You can accurately explain biodiversity, habitat, ecosystem, biome, adaptation, food web, fragmentation, invasive species, and conservation in your own words.
Skills: You can observe carefully, record data, compare habitats, build food webs, interpret simple evidence, and explain cause-and-effect relationships.
Products: Your maps, models, posters, surveys, diagrams, videos, or written explanations show clear scientific reasoning and correct use of key vocabulary.
Transfer: You can use what you learned to analyze a habitat you have not studied before and suggest actions that could protect biodiversity there.
Reflection: You can identify limits in observations or data and explain what additional evidence would improve your confidence in a conclusion.

OERs on the Topic

You can also explore Habitat, Ecosystem, Biome, Food web, Pollination, Habitat fragmentation, and Conservation biology as connected topics.

Linked Learning Areas

Biodiversity and Habitats

This topic connects science with geography, environmental studies, mathematics through field data, English through explanations and presentations, art through models and diagrams, and citizenship through community conservation projects.

aiMOOC Projects