Audie's Audacious Arthropods

Audie Choi Mitcham PAP Bio 6th

Aims of this Arthropod Activity...

The objective for this lab is to find similarities between the crayfish and the grasshopper that may be phylum traits, as well as differences between the crayfish and the grasshopper that may be class traits (as grasshoppers belong to the class Insecta while crayfish belong to the class Crustacea).

Ah, the Astacoidea!

The crayfish (of the kingdom Animalia, phylum Anthropoda, class Malacostraca, order Decapoda, and superfamily Astacoidea) is a small crustacean that can be found in freshwater environments in North America.


The crayfish is characterized by its yellow-brown shell and "stem" eyes. It is said to resemble a small lobster.


Crayfish are omnivores and scavengers, so they feed on a vast range of organisms: dead plants/animals, small fish, shrimp, worms, insects, snails, plankton, etc. The crayfish is preyed upon by animals like the alligator, raccoon, snake, muskrat, and opossum.

Crazy Crayfish Facts!

  1. The crayfish can be referred to as a "crawdad" or a "crawfish" depending on where the crayfish is found.
  2. The crayfish thrive in moving bodies of water.
  3. The crayfish is a fast swimmer, thanks to its rear tail.
  4. The crayfish rarely kills anything that is alive- it's very lazy.
  5. The crayfish does all of its travelling/feeding during the darkest hours.
Crayfish Anatomy Part 1

The Crayfish's Respiratory System

The crayfish has gills, enabling it to breathe underwater. The crayfish has gills outside of its body and attached to the walking legs (as illustrated by the picture to the right of this passage), which allows the crayfish to breathe and walk simultaneously.

Crayfish and Humans

Many people around the globe eat crayfish. Crayfish season is, in fact, this month- April! People also use crayfish as bait, although that has a negative impact (the crayfish "eliminates native species"). The occasional person even keeps crayfish as a pet.

Caelifera Corner

The grasshopper (of the kingdom Animalia, phylum Anthropoda, class Insecta, order Orthoptera, and suborder Caelifera) is an insect that can be found in dry, open habitats (or all continents except Antarctica).


The grasshopper is characterized by its antennae, pinchers, and hind femurs that rub up against its abdomen to create a very distinctive sound.


The grasshopper is a primary consumer and has a diet of grasses, leaves, and cereal crops. Grasshoppers are typically polyphagous, and most grasshoppers will eat from multiple host plants daily. The grasshopper is preyed upon by animals like the beetle, skunk, shrew, toad, and snake.

Grasshopper Gospel!

  1. Grasshoppers have ears on their stomachs.
  2. Grasshoppers existed before dinosaurs did.
  3. Grasshoppers can jump up to 20 times their own height.
  4. Grasshoppers "spit" a peculiar brown liquid in self-defense.
  5. Grasshoppers can't actually distinguish between different pitches very well.
Grasshopper Dissection

The Grasshopper's Respiratory System

The tracheal system is responsible for the exchange of gases in a grasshopper. This process starts at the spiracles (where air is taken in), with oxygen diffusing into the cells directly from the atmosphere (thereby completing respiration, a fairly simple process for the grasshopper). The organs involved in this system are the:


Spiracles- small openings from the tracheae that are surrounded by hair (which serves as a filter) and valves (which are opened/closed voluntarily by the grasshopper)


Tracheae- a collection of air-filled tubes where CO2 and oxygen are exchanged


Air sacs- temporary storage spaces for the oxygen that passes through the grasshopper's body

Grasshoppers and Humans

As a result of grasshoppers being primary consumers, grasshoppers provide food for other insects, birds, and mammals. Grasshoppers naturally fertilize the soil and make up part of the diet of people from Africa, Asia, and the Middle East.

Cited Sources