By Clarise Trinh, Guzman PAP BIo P4
Crayfish live in ponds, lakes, streams, and rivers and live all around the world. They are very durable animals and can tolerate a wide range of temperatures and salinities. However, crayfish are very intolerant of any pollution of their environment. Crayfish eat aquatic plants, mollusks, insect larvae and adults, tadpoles, and small eggs. Crayfish tend to hunt for food at night. Crayfish moult - shedding and regrowing their exoskeleton. Raccoons, foxes, muskrats, snakes, turtles, and birds eat crayfish. Crayfish are very important to stream ecosystems and maintain a high level of water quality by feeding, foraging, and burrowing.
Grasshoppers feed on a variety of plants. Bird, lizards, spiders, and rodents eat grasshoppers. Grasshoppers are ectothermic and have bilateral symmetry. Grasshoppers are found on all continents except for Antartica. They go through incomplete metamorphosis and shed their skin. Grasshoppers can be crop pests because they can eat so much plant material. Grasshoppers have two pairs of wings and large eyes. Males have special structures on their wings that produce sound when rubbed together. Females are larger, but males are more colorful
Arthropods are a highly successful group of animals—they account for over three quarters of all currently known living and fossil organisms.
Arthropods have an open circulatory system.
When arthropods grow, they must molt their exoskeleton.
Arthropods go through metamorphosis.
The word arthropod means 'jointed feet'.
Arthropods do not possess blood vessels.
Arthropods are divided into four basic groups: Myriapods, Chelicerates, Hexapods, and Crustaceans.
The oldest arthropod known to have lived on land is the Pneumodesmus newmani.