Science2 - 00050

Science2 - 00050 - Untitled In the dim and distant past...

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Untitled In the dim and distant past there was a time when the only animals were of the nature of Protozoa, and it is safe to say that one of the great steps in evolution was the establishment of three great types of Protozoa: (_a_) Some were very active, the Infusorians, like the slipper animalcule, the night-light (Noctiluca), which makes the seas phosphorescent at night, and the deadly Trypanosome, which causes Sleeping Sickness. (_b_) Others were very sluggish, the parasitic Sporozoa, like the malaria organism which the mosquito introduces into man's body. (_c_) Others were neither very active nor very passive, the Rhizopods, with out-flowing processes of living matter. This amoeboid line of evolution has been very successful; it is represented by the Rhizopods, such as Amoeb± and the chalk-forming Foraminifera and the exquisitely beautiful flint-shelled Radiolarians of the open sea. They have their counterparts in the amoeboid cells of most multicellular animals, such as the phagocytes which migrate about in the body,
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This note was uploaded on 10/05/2009 for the course MATH 205 taught by Professor Popescu,c during the Fall '08 term at UCSD.

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