When ectoparasites first arrive and adapt to the fur or feathery habitat of a host, they often lose more complex ancestral features. So it is possible to gain a trait in evolution and subsequently lose it. However, it is considered vastly improbable that this same trait will again re-evolve. Therefore, in trying to trace evolutionary lineages, can we always expect the most primitive forms to be the simplest and the most advanced to be the most complex? Why or why not?
What will be an ideal response?
We cannot definitively say that the most primitive forms are the simplest and the most advanced forms are the most complex. A perfect example of this is when ectoparasites lose more complex ancestral features as they adapt to the new habitat of their hosts. It is therefore possible to gain a trait in evolution and subsequently lose it. A more advanced form may actually lose traits in the process of evolution and appear to be more primitive.
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Fill in the blank with the appropriate word.
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a. hold water. b. control soil erosion. c. control flooding. d. control sediment buildup in lakes, rivers and reservoirs. e. all of these.
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Answer the following statement true (T) or false (F)