ANIMALS

LAMARCK’S AND DARWIN’S EVOLUTION THEORIES

VOCABULARY

NECK

TREELEAVES

ADJECTIVES

SHORT

LONG

SHORT NECKED GIRAFFE

LONG NECKED GIRAFFE

ACTIONS

REACH (THE SKY)

STRETCH

GROW

LAMARCKLamarck's Theory:  Giraffes inherited long necks from short necked ancestors who continually stretched their necks to reach food.

LAMARCKLamarck's Theory:In the very beginning, giraffes had got short neck and they used to eat leaves from short trees. Then, trees started to grow taller and taller and giraffes couldn’t reach the leaves, so that, they had to stretch their necks to try to reach them and eat. That is, giraffes evolved from short to long necks throughout time (history).

Darwin's Theory:  Long necked and short necked giraffes once existed together, but long-necked giraffes had an adaptive advantage.

DARWIN

Darwin's Theory:  Long necked giraffes and short necked giraffes existed together, but short necked giraffes disappeared because they were very hungry and they couldn’t reach leaves from trees, so they died; and long necked giraffes survived. This is why we only see giraffes with long necks nowadays.

DARWIN

LAMARCK

DARWIN

DARWIN’S THEORY OF EVOLUTIONAnimals change over time in order to survive where they live. So, fish evolved to have gills because they needed to be able to breathe underwater. Some animals evolved to have sharp teeth or big claws so they could kill their dinner. Other animals evolved with scales or shells to protect themselves and not get eaten as dinner. Others evolved to fly or climb to get away from danger altogether. As people were evolving from chimpanzees, we didn’t get any of those things.Instead, we got really, really smart brains. And we survived because we

used those brains to think our way out of trouble. Plus, because we evolved to walk on 2 feet instead of 4, we wound up with hands that, combined with our smart brains, allowed us to do things like build houses, make clothing and weapons and — eventually — invent really important stuff.