OCN EXAM 2022/2023 with 100% correct answers

Which statement is true? A. Human ancestors with more diverse diets were more likely to go extinct during times when environmental conditions change. B. The proposed hypothesis of variability selection states that the key events in human evolution were shaped by environmental instability and the flexibility of our ancestors in what they ate and where they lived. C. The savanna hypothesis states that Hominin speciation was driven by abrupt and fast climate fluctuations of wet-dry cycles. D. Savannas are desert-like ecosystems composed of shrubs and xerophytes common in East Africa. - ANSWER-B. The proposed hypothesis of variability selection states that the key events in human evolution were shaped by environmental instability and the flexibility of our ancestors in what they ate and where they lived. What evidence allowed scientists to refute (disprove!) the hypothesis that bipedalism and increased brain size were driven by a single, gradual long-term trend towards increased aridity and the expansion of the savanna? A. Paleo diet research of fossil tooth isotopic data. B. Plant wax biomarkers in sediments. C. Carbon 13/12 isotopic ratios of C4 grasses versus C3 woody plants in sediments. D. Adaptations of Bovids (African antelopes) in the fossil record. E. Layers from deep-sea sediment cores. - ANSWER-All of the above Lake Turkana is located in a region with most of the fossil record of early human origins and contains sediments that can be used to study past climate fluctuations. True or False - ANSWER-True Homo erectus was in the same genus as Homo sapiens, but had different skull morphology. True or False - ANSWER-True Match the name and description with the route 1. Northern Route 2. Southern Route A. Crossing the Red Sea near Bab-el-Mandeb to reach the Arabian Peninsula. B. Crossing the Sinai Peninsula to reach the Levant. - ANSWER-B= Northern Route A= Southern Route Which statement is false? A. Homo erectus was much larger than Homo sapiens and was extinct when Homo sapiens emerged. B. Green Sahara periods can be identified through dust records from marine sediments. C. Migration out of Africa through the northern and southern routes occurred in waves. D. Green Sahara periods were caused by stronger Northern Hemisphere seasons (warmer summers) and stronger African monsoon. E. Green Sahara periods allowed for a North African corridor and migration out of Africa. F. Green Sahara periods can be identified through cave paintings and fossils of hippos and crocodiles in North Africa regions that are now in dry desert climate (e.g. the Sahara Desert). - ANSWER-A. Homo erectus was much larger than Homo sapiens and was extinct when Homo sapiens emerged. Around 100,000 years ago archaic humans (the variety of Homo species before modern humans) first left Africa. True or False - ANSWER-False What traits may have allowed early human ancestors to first leave Africa? - ANSWER-A. Intelligence B. Diet with more meat C. Striding gait D. Tools Why is the Levant (a historic area in the Eastern Mediterranean) important? - ANSWER-A. It was intermittently occupied by early humans during the waves of migration out of Africa. B. It is the crossroads of Western Asia, the Eastern Mediterranean, and Northeast Africa. C. It is where Homo sapiens first encounter archaic humans outside of Africa. Match the item with its significance or explanation. A. The 'highway' that allowed Homo sapiens to migrate to Europe. B. Evolutionary cousins to Homo sapiens. C. The time of arrival of Neanderthals in Eurasia. D. The time of arrival of Homo sapiens in Europe. E. The amount of shared DNA between present-day humans of primarily European and Asian descent and the now extinct Neanderthals. - ANSWER-1. 1-2%= E 2. 400,000 years ago= C 3. 40,000 years ago= D 4. Danube River= A 5. Neanderthals= B Neanderthals were better adapted to the colder climate in Eurasia because of their tall and slim body shape which helped them conserve heat. True or False - ANSWER-False How did climate affect the survival of Homo sapiens versus Neanderthals? A. Homo sapiens were likely more successful in utilizing scarce glacial food resources as compared to Neanderthals, thus outcompeting and slowly absorbing them into their species. B. Homo sapiens were better adapted to a colder climate because they had large nasal chambers that helped warm and humidify the cold and dry air. C. Homo sapiens had higher reproduction rates and resulting faster migration speeds which allowed Homo sapiens to move away from areas that underwent a rapid decline in food resources due to rapid past climate changes and re-populate elsewhere. D. A and C are correct. E. All answers are correct. - ANSWER-D. A and C are correct. Which statements are true? A. Neanderthals died out because they were primitive and inferior to Homo sapiens, lacking any social organization or ability to use tools, fire, art, and language. B. Neanderthals had complex cognitive abilities and behaviors possibly including rituals. C. Genes that some humans inherited from past interbreeding with Neanderthals can control susceptibility to certain diseases. D. All genes that are inherited from Neanderthals are harmful to modern humans. - ANSWER-B. Neanderthals had complex cognitive abilities and behaviors possibly including rituals. C. Genes that some humans inherited from past interbreeding with Neanderthals can control susceptibility to certain diseases. Since carbon dating is only accurate to 50,000 years ago, scientist Sophie Verheyden measured uranium levels of broken stalagmites to date the presence of Neanderthals in the Bruniquel Cave in France (approximately 175,000 years ago!). True or False - ANSWER-True Why do scientists study Neanderthals (Homo neanderthalensis)? A. Neanderthals are still alive today. B. Homo sapiens evolved from Neanderthals. C. Neanderthals are distant cousins and their behaviors and evolutionary history hold clues to our own identity as Homo sapiens. D. Neanderthals were basic and unsophisticated. E. Neanderthals never crossed paths with Homo sapiens. - ANSWER-C. Neanderthals are distant cousins and their behaviors and evolutionary history hold clues to our own identity as Homo sapiens.