Convergent Evolution: Why bears and seals are more similar than you thinkScience project video

popular science fair projects
Complexity level:
8
Project cost ($):
Time required:
Material availability:
Safety concerns:

Abstract

Convergent evolution refers to how different species of organisms evolve to possess similar physical characteristics, in order to adapt to a particular environment. At first look, bears and seals may appear to have little in common other than both of them being mammals. Yet, the skeletal structures of their feet are very similar. In this investigation, you will select a biome and identify a convergent species.

Objective

Identify a convergent species.

Background

Convergent evolution is the study of how different species develop similar physical traits in order to adapt to similar environmental conditions. Biomes are biological communities that are distinguished by climatic conditions and the species that inhabit it. One category of biomes are the deserts. Whereever deserts occur in the world, they all share similar environmental conditions, one of which is an abundance of sand or sand dunes. The sidewinder is a species of viper that lives in the deserts of the south western United States. The sawscaled viper of Africa is an entirely different species of snake; however, both the saw-scaled viper and the sidewinder employ the same distinct sideways motion in order to gain traction across the desert sands. Both species have adapted to the same environmental conditions by using the same strategy. But the physical features that are shared by convergent species may also include internal similarities - for example, the paws of the bear and the flippers of the seal share the same bone structure.

Scientific Terms

Convergent evolution, Biome

Materials

Internet access

Procedure

Note: Refer to the resources under the bibliography section as well other online resources to conduct this investigation.

  1. Identify a biome:
    • Desert
    • Savannah, prairies and grassland
    • Forest and woodland
    • Tropical rain forest
    • Mountains
    • Fresh water
    • Ocean
    • Tundra
  2. Identify two different continents that contain the biome you selected.
  3. Research the characteristics of the biome such as:
    • Weather conditions
    • Annual Rainfall
    • Temperature
    • The plant life that characterizes the biome
  4. Research the species that inhabit the selected biome for both continents.
  5. Select two different species, one from each continent that you believe may share similar physical characteristics. Consider both internal and external physical characteristics:

External:

  • Limb structure
  • Shape of teeth or beaks
  • Claw size
  • Tail: Prehensile, flattened, or longer than body length.
  • Skin features: (Example: Scales, armor, or fur length).

Internal

  • Bone structure
  • Specialized stomach
  • Note: The previous list are just examples and not exclusive of all the possible adaptive characteristics.

 

Form a conclusion as to whether the shared physical characteristics are consistent with the demands posed by the selected biome.

Discussion

Both evolution and convergent evolution reveal how species respond to the pressures of the environment. Do you think that environment shapes behavior and the physical makeup of a species, or does the species intentionally develop adaptations to fit the environment? Do you think that the environment plays an active role in molding the physical make-up of a species and that the species undergoes a calculated change in response to environmental conditions, or do any adaptive changes occur by chance.

Questions & Answers

What is the difference between a biome and a habitat?

A biome is a larger, more regional area that is characterized by distinct climate and biological communities. Smaller than biomes, habitats are the local areas within the biome that specific species inhabit.

Make it Your Own

Conduct similar research on convergent evolution in humans.

References

Videos