Invertebrates comprise most of the species on earth and are often the most abundant animals in an ecosystem. Before students head outside to explore the ecosystems in your area and the invertebrates living in them, it’s important for them to learn more about both. They should use the resources on their Outdoor Science student esheet and the book to answer the questions on their student sheet.
Students should read page 109 in the book and watch the video Ecosystems from Scholastic. As they read the page and watch the video, they should think about answers to these questions.
What is an ecosystem?
It is a community of animals and plants interacting with their environment.
What does an ecosystem consist of?
It consists of primary producers, consumers (primary consumers = herbivores, secondary consumers = carnivores), and biotic and abiotic factors. Students can also list various organisms.
What does "abiotic" mean? Provide a few examples of abiotic factors in an ecosystem.
Abiotic means nonliving. Some examples are rain, sunlight, minerals in the soil, and temperature.
What does "biotic" mean? Provide a few examples of biotic factors in an ecosystem.
Biotic means living. Some examples are plants, animals, and bacteria.
Why are healthy ecosystems important?
All living things, including humans, need healthy ecosystems for survival. Resources available on Earth are limited, and what happens in one ecosystem often impacts others. There is usually a delicate balance between all living and non-living things (or factors) in an ecosystem, and disturbing that balance, e.g., by changing the environment, introducing new species, etc., will affect the diversity of species in the ecosystem.
Students should read page 35 in the book and read the first paragraph of the Encyclopedia of Life Invertebrate webpage.
What characterizes invertebrates?
Invertebrates are animals without backbones like bugs, worms, snails, corals, sponges, and many other obscure squiggly and crawly things.
How many (in percent) of the animal species we know today are invertebrates?
95% of the 1.4 million known animal species are invertebrates.
What animals are invertebrates?
Among invertebrates, arthropods (insects, crustaceans, spiders, and relatives) are by far the most diverse group with more than 1.2 million living species. Others are worms, snails, corals, squids, mussels, jellyfish, sea stars, sea anemones, sponges, and single-celled creatures called protozoa.
Which of these invertebrates can you find on land? And which ones might live in your backyard?
Insects (including caterpillars—the larval stage of butterflies and moths), spiders, ticks, silverfish, earthworms, snails, and slugs are all found on land and are very likely inhabiting your backyard. (Students may remember the names of some of them, such as stinkbugs, lady beetles [incorrectly known as ladybugs], dragonflies, daddy longlegs, banana slugs, cockroaches, cicadas, grasshoppers, etc.)