Life Cycling Pre-site Activity #2

Comparing Life Cycles - Pre-site Activities/Teacher Led

Grade Level: 2
Content Area: Science
Time to Complete: 30 minutes
Title of Lesson: Comparing Life Cycles

South Carolina State Standards Addressed:

2-1.1	Carry out simple scientific investigations to answer questions about familiar objects and events.
2-1.3	Represent and communicate simple data and explanations through drawings, tables, pictographs, bar graphs, and oral and written language.
2-2.1	Recall the basic needs of animals (including air, water, food, and shelter) for energy, growth, and protection.
2-2.2	Classify animals (including mammals, birds, amphibians, reptiles, fish, and insects) according to their physical characteristics.
2-2.5	Illustrate the various life cycles of animals (including birth and the stages of development).

Lesson Description:

Students will investigate and compare life cycles, using picture cards that show the life cycle stages of a frog, a butterfly, and a chicken.

Focus Questions for Students:

1.	How are the frog, the butterfly and the chicken life cycles alike?
2.	How are the frog, the butterfly and the chicken life cycles different?
3.	Which of these animals goes through metamorphosis, and looks very different from its parent after hatching from an egg?
4.	In what ways does a frog need good water as an egg, as a tadpole, and as an adult?

Culminating Assessment:

1.	Students will be able to describe how the frog, butterfly and chicken life cycles are alike: each hatches from an egg, each needs food, air and water to survive, the butterfly and chicken both have wings as adults, the frog and butterfly, being cold-blooded, are very dependent on temperature, the frog and butterfly both go through stages where they look very different from their parent, etc.
2.	Students will be able to say that there are certain differences between the frog, butterfly and chicken life cycles: The frog has jelly-like eggs in water, but the butterfly and chicken have eggs on land. One has thin-moist skin, one has scaly insect wings, and one has feathers,.etc.
3.	Students will be able to say that the frog and the butterfly go through metamorphosis.
4.	Students will be able to say that a frog starts out as maybe one of thousands of jelly-like eggs in the water. As a tadpole, it lives and breathes in the water with gills. As an adult, it may or may not live in the water, but must be in some water or moist leaves, etc. to soak up water in its skin. At all stages, polluted water would harm or kill the frog.

Materials/Equipment:

6 sets of life cycle picture cards: 2 each of a frog’s life cycle, 2 each of a butterfly’s life cycle, and 2 each of a chicken’s life cycle.
worksheets

Teacher Preparation:

1.	Read background information.
2.	Be prepared to introduce the life cycles of a frog, butterfly and chicken.

Background Information:

Some animals resemble their parents at birth, while others go through metamorphosis. Metamorphosis means to change in form during the growth of an animal. Frogs go through this process as they change from one of thousands of jelly-like eggs in a lake or other water area, into a tadpole that breathes in the water with gills and eats algae plants, gradually developing back legs, then front legs, and finally becoming a hopping, lung-breathing, animal-eating adult frog. During all stages of a frog’s life cycle, it needs good, unpolluted water to survive.

A butterfly goes through what is referred to as complete metamorphosis, going through 4 distinct stages. It starts out as an egg, laid by the mother. She lays the egg on the leaf of a certain plant. When the egg hatches into a caterpillar (the larva stage), it can only eat certain species of leaves, and it starts out on the correct kind. The caterpillar eats and grows, until it reaches a certain size. When it is the right size, it finds a suitable plant on which it creates and attaches it chrysalis (the pupa stage), which it makes from its own body (moths often make a cocoon out of a leaf). Finally, it emerges from the chrysalis as an adult butterfly. Some butterflies, like the monarch in this set, migrate long distances to survive the winter, while others live just a couple weeks then die. At all stages, the butterfly is very dependent on plants, and a protected habitat.

Other insects found in the lakes or streams at Paris Mountain State Park include beetle

larva, and dobsonfly larva, which also go through these four stages of metamorphosis.

Some insects found here go through ‘incomplete metamorphosis,’ with just three stages instead of four: egg, nymph, adult. Students frequently find dragonfly nymphs, mayfly nymphs, and stonefly nymphs.

The chicken is not found at Paris Mountain State Park. Many birds do live around the lake and stream areas, including ducks, geese, hawks, and many songbirds. They all lay eggs in nests, hatching into a creature that has feathers, wings and a beak like its parent, though the feathers are downy at first. Birds are taken care of by their parent during at least the first couple weeks of life, sometimes much longer.

Procedures:

Note: If you like, make copies of the worksheet either for each student or for each group.

1.	Discuss life cycles with students, stating that every animal goes through a life cycle. Some animals look sort of like their parents when they are born, while others look very different, and change form as they grow (metamorphosis). Every animal needs food, water, and shelter to go through its life cycle.
2.	Divide students into 6 groups of 5 or less. Hand out the 6 sets of life cycle picture cards (out of sequence). Two groups will have the frog life cycle set, 2 groups will have the butterfly life cycle set, and 2 groups will have the chicken life cycle set.
3.	Ask students to put their set in the correct order from youngest to oldest.
4.	As a class, discuss the stages of each type of animal. What does it start out as? Where would you find this type of egg (habitat)? What is the next stage for each? If you like, discuss a butterfly’s life cycle, with the 4 stages, and compare to that of a dragonfly with just the 3 stages.
5.	Discuss how the frog, butterfly and the chicken are alike, and how they are different.
6.	Discuss how the habitats of each are alike or different.
7.	Students fill out the worksheet.

Other Possible Activities:

1.	Mix up all the picture cards, and hand one to each student. Have the students walk around and find others with the same animal they have, and then put them in order.
2.	Using two of the types of animals, make a Venn diagram on the board, drawing 2 circles that overlap in the middle, and labeling each circle with the name of the animal. Have students state characteristics of each animal. On the outer part of each circle, write statements specific to one of the animals. On the overlapping middle part, write statements specific to both animals.
3.	Students can draw a picture, placing their animal in the picture at some stage of its life cycle – emphasizing habitat.