Key concepts
Have you ever wondered how many different types of animals live near you—in your backyard or a local park? And we're not just talking about deer or even birds. Animals come in all shapes and sizes—from big bears down to the tiniest bugs—each a unique part of the amazing diversity of life. The differences among animals can help us classify animals into different groups. One way people classify animals is by their phyla. Do you know which phylum you belong to? What about a garden spider? In this science activity you'll investigate the biodiversity of the animal life around your home and try to figure out to which phylum most of the animals belong.
From the largest elephant to the tiniest water flea all animals have unique characteristics. Based on their shared characteristics animals are put into categories called "phyla." (A phylum is specifically a taxonomic ranking, which appears between kingdom and class in the traditional hierarchy of ranks.) There are perhaps as many as 35 different phyla within the animal kingdom alone but most are very uncommon. Scientists recognize eight major phyla to describe most common animals: Porifera, Cnidaria, Platyhelminthes, Annelida, Mollusca, Arthropoda, Echinodermata and Chordata. These names might sound foreign at first, but once you find real-world examples close to home some should start to become much more familiar!
Depending on where you live the phyla you encounter most frequently may be Chordata, Arthropoda, Mollusca and Annelida. Chordata is the most well known group, even though it is quite small in the number of individuals it contains. Have you guessed which one it is? It is the phylum that includes all of the vertebrates and thus is the phylum we belong to—along with most of our pets (dogs, cats, rabbits, rats, fish, frogs, salamanders), farm animals (cows, pigs, sheep, chickens) and zoo animals (zebras, lions, tigers, pandas, giraffes, polar bears, etcetera). Arthropods are invertebrates and include insects (such as beetles, butterflies, flies, bees, wasps, grasshoppers and ants) as well as centipedes, millipedes, spiders, shrimp, crayfish, pill bugs and many others. Mollusca includes snails, slugs, bivalves (such as clams and oysters), squids and octopuses. Annelids are segmented worms and include earthworms (which are used for compost and gardening) and aquatic worms. What phylum do you think is most common around you?

  • Sheet of paper
  • Pencil or pen
  • Digital camera (optional)
  • Magnifying glass (optional)
  • An observation location
  • Choose your observation location. It should be a place you like to explore and where you think you might find a diversity of organisms. It could be a backyard, park, community garden, open field, lake, stream, etcetera where you are allowed to poke around.
  • Pick a good time to do your investigation and bring along an adult supervisor if need be.
  • Bring your sheet of paper and pen or pencil (and digital camera and magnifying glass, if desired, along with an adult, if necessary) to the observation location you decided on.
  • Pick a small part of the location to investigate first. For example, it could be a pile of dead leaves, some shady rocks, a patch of lawn, old logs, dry weeds, a tree, etcetera. (These are all different "microhabitats.") You will be able to choose additional microhabitats to investigate later.
  • Carefully look for animals in the microhabitat you picked. You may want to turn over rocks or logs to look for animals underneath them. On your sheet of paper write down what type of animals you see. (For example, maybe you see a bird, earwigs or spiders.) Do not worry if you cannot identify something right away—you can write down a description, make a drawing or take a picture and try to identify it later. What animals do you see? What kind of microhabitat are they living in? (Is it dry, damp? Does it have plants, rocks, etcetera?)
  • Move on to another microhabitat and similarly investigate it. What animals do you see in this area? Do any of the animals look like different species of types you saw already? What is this microhabitat like and how is it similar or different from the previous one?
  • Repeat your observations in other microhabitats—trying to find ones that are very different (sunny versus shady or dry versus damp, for example) and some similar (both shady or both dry, for example). Try to explore at least five different microhabitats at your observation location, if possible. Do some animals seem to prefer certain types of microhabitats (such as damp ones or dry ones) more than other animals?
  • Once you're done investigating the observation location, try to categorize the animals you found by their phyla. Depending on what your observation site is, the phyla you are most likely to encounter are Chordata, Arthropoda, Mollusca and Annelida. Remember that chordates include all vertebrates (including us, dogs, cats, frogs, fish, cows, birds, etcetera); arthropods include insects, centipedes, millipedes, shrimp, pill bugs, etcetera; mollusks include snails and slugs; and annelids include earthworms.
  • For which phylum did you find the most kinds of animals (that is, greatest number of different species)? Which phylum was the most difficult to find? Were there some phyla that you couldn't find at all? How diverse do you think animals are in your region? Did you consistently find certain animals in a specific type of microhabitat?
  • Extra: In this activity you investigated a single observation location with different microhabitats but you could also try surveying two or more separate locations and compare the microhabitats within them. How do your local parks compare with one another? If you live near water, how does a shoreline compare with a park’s grass and trees? How do the species’ diversity change? (Tip: If you investigate a marine location, you'll want to do some background research on other common phyla that might live there.)
  • Extra: Make a species map to figure out how different animals are distributed in your observation location. To do this, first make a map of your observation location, marking locations of structures such as your house, a patio, shed, trees, etcetera, and make several copies of the map. Then repeat this activity but this time investigate the entire location and use a different copy of the map for each different type of organism you find, coloring in the map where you find that type of organism. What types of areas do certain species seem to prefer? Which areas have the most different kinds of species (or most biodiversity) and which have the fewest (or least biodiversity)?
  • Extra: Your wildlife observations can be helpful for several different citizen science projects. Follow the links to see how you can contribute your investigations, for example, to: What's Invasive!, the Lost Ladybug Project, School of Ants, Bee Hunt!, Project Squirrel, Project FeederWatch or Wildlife Sightings. (For more opportunities to contribute to big projects, check out the Citizen Science list from Scientific American.) What invasive organisms are in your area? What are your local populations of ladybugs, ants, bees, squirrels, birds and other wildlife animals like?

Observations and results
Did you mostly find arthropods at your observation location?
The types of animals you saw depends on your observation location. But for most backyards, parks, gardens, fields, etcetera the phylum that the majority of the different animals belongs to is Arthropoda. Some of the most common arthropods you would see in North America include various flies, beetles (including ladybugs), spiders, roly-polies, grasshoppers, centipedes, millipedes, earwigs, ants, butterflies, wasps, crickets and many others. You might also have seen snails and slugs (which belong to the Mollusca phylum). If you dug around in the soil, you may have uncovered earthworms (part of the Annelida phylum). And if you counted yourself in your survey, then you also found at least one member of the phylum Chordata! Other common chordates you may have seen include squirrels, birds, dogs and cats.
More to explore
Finding Phyla, from Science Buddies
Animal, from Science Clarified
Biodiversity, from National Geographic Education
Science Activities for All Ages!, from Science Buddies

This activity brought to you in partnership with Science Buddies