What Darwin Never Knew - Answers PDF

Name: _________________________ NOVA Documentary: What Darwin Never Knew This documentary is an awesome introduction to evolution and explores the topic from multiple directions. Read the questions below before the movie begins. As you watch the documentary, answer the questions in point form. These...

Name: _________________________ NOVA Documentary: What Darwin Never Knew This documentary is an awesome introduction to evolution and explores the topic from multiple directions. Read the questions below before the movie begins. As you watch the documentary, answer the questions in point form. These can serve as useful notes for this content! 1) Why did Charles Darwin decide not to become a doctor as his father had hoped? He was too squeamish. 2) What did he study after giving up medicine? He joined the clergy 3) What is the name of the ship that Darwin was offered a spot on? HMS Beagle 4) What was this ship’s mission? To survey the waters around South America. 5) How long did the voyage last? 5 years 6) Where did he make his first important discovery and what was it? Argentina. He found the fossils of giant, extinct mammals and wondered what their relationship was to living animals. 7) Where was the most important area of Darwin’s research? Where is it located in the world? Galapagos Islands, Ecuador 8) Describe one animal that only exists in the Galapagos Islands? Giant tortoises, marine iguanas, etc. 9) How can locals determine which island a tortoise comes from? They have unique shell patterns. 10) What did Darwin begin to collect? Finches 1 11) How many species of finches did he collect? How come he did not initially realize they were all finches? 14; they were all different. 12) What conclusion did he draw about finches’ beaks and tortoises’ shells? Different species are found on different islands. 13) What had Darwin found in the ground of South America? Buried ancestors of living animals in South America. 14) Describe Darwin’s observations from looking at a human embryo. Embryos all look similar, but they develop differently. For example, tiny slits in the neck become gills in a fish and bones of the ear in humans. 15) What did differences in dog size lead Darwin to propose? The range of size did not come by chance, but from specific breeding. Natural selection could explain the diversity of life! 16) How did Victorian society view nature? How did Darwin view nature? Victorian society viewed nature as friendly, while Darwin viewed it as a battlefield. 17) What did Darwin notice about the creatures who survived battles with other species? The winners were those that were best suited to their environments. 18) Why do the finches have beaks of different sizes and shapes? Their beaks are suitable to eat the food on their islands. It appeared that one type of beak transformed into many. 19) What did Darwin realize about variation? Variations accumulate and branch off to create new species. 20)What happened to the fur of the mice in the Arizona desert? Black-furred mice live on black rock; white-furred mice live on white rock. 2 21) Why is mutation of DNA important in evolution? Mutation leads to variation. 22) Are mutations bad? Why or why not? No! They can be good, bad, or neutral. 23) How many genes are in humans? ~23 000 24) Why are large mammals not good candidates to study in the laboratory? They can be hard to house and reproduce too slowly. 25) Why did the paintbrush gene makes spots in one type of fruit fly but not the other? Different gene switches (mutations in a few letters of DNA) are turned on in different fruit flies. 26) How much of the genome does not code for proteins? 98% 27) What is a gene switch? A piece of DNA that turns a gene on or off but does not code for a protein. 28) What happens inside the embryo to determine what type of finch will form? Certain switches are turned on/off in each type of beak. 29) What fossil did Neil Shubin hope to find? What would this prove? A fish that walked (i.e. part fish with the beginning of legs). This type of transitional fossil would be a link between life on land and in the water. 30) Why did he decide to look in Elsmere Island? It is close to the North Pole and has exposed rock that was dated as close to the time when fish moved to land. 3 31) What did the flat-headed fish with upstaring eyes indicate? That the animal was able to push its head out of the water. This was a 375 million year old fossil. 32) What did they name this fossil? What does the name mean? Tiktaalik. It is Inuit for freshwater fish. 33) Why do they think the fish wanted to get onto land? To get away from predators. 34) Were they able to get DNA from this fish? Which fish did they use instead? Why did they select this fish? No. Instead, they used paddlefish. These long snouted fish are the last survivors of the class to which Tiktaalik belonged and should thus share a lot of genes. 35) What are Hox genes? Body patterning/plan genes. They are found in all complex animals. 36) What was the name of the orangutan that was in a zoo near Darwin? Jenny. He saw human behaviors in her. 37) What is the difference between our DNA and that of chimpanzees? 99% identical, 1% different. 38) What makes the human hand so special? We can touch all of our fingers with our thumb. It allows for dexterous and nimble activity. It allows for precision and power. 39) When the DNA sequence that differs from chimpanzees at 13 places was discovered, what did the scientist decide to do with this DNA? He inserted it into the embryo of a mouse. 40) What did he do in order to track it in the mouse embryo? He attached it to a protein with a blue color. 4 41) What did it do in the growing paw? It was active in the thumb and the big toe. It showed there was a switch that helps to form our thumb. 42) How does the human brain differ from the chimp brain? The human brain is 3X bigger than a chimp brain. 43) What has Hansel Stedman dedicated his career to? Curing muscular dystrophy. 44) What was strange about the gene that Stedman found? 2 letters of the DNA were missing, which he thought should cause a disease in muscle! He learned that he had the same mutated DNA. 45) What is the role of this gene when he observed it in chimps? It is part of the muscle that is used to close the jaw. This was interesting as the human jaw is much less powerful that the chimp jaw. 46) Why do the chimp brain growth plates closed earlier than that of humans? The powerful jaw muscle pulls against the plates and makes them close earlier. This means that the brain can’t grow as long in chimps, as the plates close by 3 – 4 years. In humans, they are open until ~30. 47) What is microcephaly? Small brain. 48) What gene did Walsh find? A gene that controls how and when brain cells divide. It directs brain growth. 49) How did the healthy human gene compare with the gene in chimps? It was radically different; there was a large series of mutations. 50) What is the cortex? What is it responsible for? It is the outer later of the brain that is responsible for a lot of characteristics that we thin of as “human” such as language, music, mathematics, etc. 5 51) What are the 3 most interesting things you learned? 52) What are 2 questions that you have about evolution? 53) What is 1 thing that you would tell Darwin after watching this documentary? 6