Hominid Evolution EQ: How do bipedalism, opposable thumbs, and skull size support Hominid evolution?

Primates Mammals with flexible hands and feet, forward-looking eyes, and enlarged brains relative to body size

Primates include… Apes Monkeys Hominids

Hominids Primates that walk upright, have long lower limbs, opposable thumbs, and large brains Includes: HUMANS in the Hominid Family

Misconceptions: Why is the statement, “we come from monkeys” incorrect?

Hominid Evolution There have been at least a dozen different species of hominids over the last five million years or so – with evidence to prove it! Homo sapiens fossils date to 200,000 years ago. Human evolution is influenced by a tool-based culture.

Hominid Trends 1. Hominids are bipedal- can walk on two legs allows for higher reach; free hands for hunting/using tools, and foraging

Thumb(less) Challenge Tuck your thumbs into your palms You may not use your thumb for this challenge. When I say, “GO!” try unwrapping your starburst.

Opposable Thumbs! 2. Opposable thumb: a thumb that can be placed opposite the fingers of the same hand. allow the digits to grasp and handle objects/tools why is an opposable thumb advantageous?

Hominid Evolution Humans have advanced over the last 100,000 years from their ancestral Hominids. What do you notice about the changes in skulls? How can these changes be an advantage? Jaw gets smaller– allows skull to grow larger and allow space for larger brains

Hominid Trends 3. Skull shape has changed to accommodate larger brains Humans have the largest brains of all primates the skull of a human has a vertical forehead, providing a large brain capacity. Smaller jaw size allowed for larger brains to develop When might having an increasingly larger brain size no longer be a selective advantage? Why would an even larger brain size not be a selective advantage? To large to support, child birth

Brain Anatomy Cerebrum includes 4 lobes Cerebellum Brain Stem Medulla Pons Medulla Oblongata

There are 4 lobes of the brain 2 1 3 Color in the lobes of the brain as the image shows COLOR YOUR NOTES! 4

QKA Scientists have found evidence that about 2.4 million years ago a gene regulating jaw muscles mutated and may have led to the more graceful human jaw we see today. The diagram below shows the skulls of 3 hominid species. Which statement below most closely explains the link between jaw size and hominid evolution? A. The jaws of hominids evolved to be smaller and less protruding over time as did the skull. B. The jaws of hominids evolved to be larger and more protruding over time. C. There appears to be no change in the jaws of hominids over time. D. The jaws of hominids changed over time due to a change in brain size

QKA The illustration shows four lobes of the human brain. What lobe is designated by label 3? A. temporal B. parietal C. occipital D. frontal

What did the gorilla call his first wife? His prime-mate

Hominid Evolution Lab Take the measurements and calculate indexes for the human, hominid, and gorilla C- level 2 voice with your partner H- ask 3 before me A- complete Hominid Evolution lab Questions in notebook M: remain at your table (may stand while measuring) P- working with your partner on measuring Not writing this down

EXIT TICKET Clear your desk of everything except do now and something to write with!

Use complete sentences. Exit Ticket How do bipedalism, opposable thumbs, and skull size support Hominid evolution? Use complete sentences. HOMEWORK: vocab