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Description & Sources

Continuity and derivations of life forms between sponge and human male.

  • Orientation : Inside / outside. First stage of polycellular organism.

  • Animation and coordination : Invention of muscle and nervous cells. Mouth and stomach.

  • Swimming worm. Bilateral symmetry. Segmentation. First internal organs.

  • Primitive Cephalochordata, formation of the spine. Differentiation of internal organs.

  • Skull (with eye) and spine is complete. Vertebrata : the nervous system is complete.

  • Formation of the Jaw. - Differentiation of fins. Chondrichthyes stage

  • Typical fish - Invention of bones and scales, the fins have complex musculation and articulations. The lateral fins will evolve to become limbs.

  • The fins evolve to fleshy members. Apparition or differentiation of lungs? First land movements?

  • Formation of the neck. Fingers appear - movement and prehension ability.

  • Land conquest. Lungs are functional, but the animal is still water-dependent for reproduction. (this one should be a salamander, not a lizard, but the general outlook is OK)

  • Dry skin and water-independence of Amniote. (this one should be a lizard, not a salamander, but the general outlook is OK)

  • Hair and gestation invention. Primitive mammalia are but insect-eaters "hairy lizards"... this one's cute, isen't it?

  • Living in trees, our ancestors gained an opposable thumb and binocular frontal vision.

  • (I needed an intermediary picture for smoother transition, so...) Higher monkey - social interaction and communication probably increased at that time. Ability to awkwardly walk on two feet.

  • (I needed yet another intermediary picture for smoother transition, sorry) Our nearest cousin - lost its tail, by the way.

  • Vertical position frees the brain and the hand.

Summary

Description Evolution line from sponge to man
Date 1 January 2007
Source Own work
Author Michelet-密是力 ( talk)

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