NCEA Level 3 Biology (91606) 2016 — page 1 of 6
Assessment Schedule – 2016 Biology: Demonstrate understanding of trends in human evolution (91606) Evidence Statement
Q Evidence Achievement Merit Excellence
ONE Skull A is older, as it has a small sagittal crest compared to Describes four named features and Explains how identified features can Discusses how the changes in the skull Skull B, which has none. The sagittal crest is a site for the location / function of Skull A, and be linked to support evidence of features have acted as selective forces attachment of large jaw muscles, which are required when Skull B, for example: bipedalism and diet: which led to evolutionary trends. the main diet of food is plant based, and is high in cellulose • Skull A, brow ridge is larger and • More central foramen magnum • The centralised foramen magnum and low nutrition, which would mean more time required to is located above the eyes gives better balance for bipedal reduces the amount of energy chew and physically process the food. Because of the large • zygomatic arch is larger in Skull movement by having the head required by large muscles to keep the jaw muscles, the zygomatic arch needs to be large to allow A and indicates muscles for a directly above vertebrae and the head balanced on the neck. This for these jaw muscles to go through. It has a U-shaped dental large jaw hips. energy can be used to run the high arch, which is common amongst earlier hominins The brow • Skull A has a larger brow ridge, energy, larger brain. (2% of the body ridge is pronounced, and is used to dissipate the stress on the • in Skull B, foramen magnum which is used to reinforce weaker mass and uses 20% of the total cranial bones caused by eating hard low nutritious plant more centrally positioned for bones to cope with the pressure on energy.) based food. better balance the cranium caused by powerful • Weakened jaw muscles are related to • sagittal crest in Skull A is There are not many teeth on Skull A, but the molars are chewing two changes in skull structure reduced but present at the top of larger to provide a larger surface area for the grinding of explained, which in turn enabled the skull but is absent in Skull B OR coarse low nutrient plant-based foods. In Skull B the canines bigger cranial vault, which created Skull B, which has a more reduced are reduced showing less need of displays. • Skull A has larger nuchal crest space for brain expansion, (as brow ridge and larger fore brain as The foramen magnum is centralised and situated further for attachment of large neck attachment of larger muscles no large chewing muscles are no forward in Skull B, suggesting Skull A is not as well adapted muscles longer selected for). longer required for the softer diet / to bipedalism as Homo erectus (Skull B) • Skull A has larger molars more nutritious food. • A change in diet (to foods that are Skull A also has a larger nuchal crest that is for the because they ate harder lower easier to chew / softer eg meat) • Smaller zygomatic arch in Skull attachment of strong neck muscles to help keep the head in nutrition value foods provided more energy / protein / B, as they would have had smaller an upright stance compared to the Homo erectus, which has • reduced canines in Skull B not nutrients which led to an increase in jaw muscles, as they ate food with a reduced / no nuchal crest, as its head is more balanced on needed because they used less brain size and cranial capacity. a higher nutrient value / softer the vertebrae (neck), which reduces the need for powerful threat displays food / less energy spent on • Adaptive advantage of increased neck muscles. • reduced frontal lobe and a larger physical digestion OR vice versa cranial capacity eg increased Because Skull A was an earlier hominin, it has a smaller facial angle in Skull A whereas for Skull A. cognitive ability / communication / cranial capacity, 350 cc. It probably ate plant material that is in Skull B increased cranial vault planning / predicting – could be a • V-shaped dental arch / smaller lower in nutrient contents. Hominins that developed from / cranium positive feedback loop. molars in Skull B, as they ate Sahelanthropus tchadensis would have access to better food, • change from U / higher quality foods / food richer in nutrition, providing more energy that a larger brain rectangular(Skull A) to V / softened by cooking and were able required. This larger brain would have given these hominins parabolic(Skull B) dental arch / to process it better before a selective advantage in gathering food, and avoiding teeth pattern / jaw shape. ingestion OR vice versa for Skull predation. The position of the foramen magnum would have A. provided better / more efficient bipedal movement, saving NCEA Level 3 Biology (91606) 2016 — page 2 of 6
energy, allowing greater movement and therefore better access to food resources. The changes to skull structure would have been a reduction in jaw / zygomatic arch size, loss of sagittal crest / reduction in brow ridge, prognathism, and tooth size etc. The weakened muscles would no longer have required a sagittal crest / large jaw for larger muscle attachment and brow ridges to compensate for larger forces from larger jaw muscles. Changes in diet was a selective force that led to weaker muscles, thus seeking nutrients from other sources that were softer, and required less chewing.
Not Achieved Achievement Merit Excellence
NØ = no response or no N1 = 1 point N2 = 2 points A3 = 3 points A4 = 4 points M5 = 1 point M6 = 2 points E7 = 1 point E8 = 2 points and must relevant evidence have first bullet point
NCEA Level 3 Biology (91606) 2016 — page 3 of 6
Q Evidence Achievement Merit Excellence
TWO Cultural evolution is the transmission of Defines cultural evolution as: Explain how these different forms of Discuss the advantages and disadvantages that knowledge from generation to generation, not • The transmission of knowledge cultural evolution are adaptive cultural evolution has had on biological passed on by genetics, but by learning. Homo from generation to generation by advantages for the species who evolution. habilis is credited as being one of the first teaching / learning or passing on employ them. • All of the cultural forms of evolution would hominins to use stone tools, called oldowan tools. of information that is not • H. habilis had a small brain and have provided adaptive advantages for the These tools had flakes struck off one side of the genetically derived. were scavengers that were able to hominin species who employed them, allowing pebble. H. habilis had a small brain and were Describes the different forms of use the stone tools to break open them a greater chance at surviving, and being scavengers that were able to use the stone tools to cultural evolution of Homo habilis, bones and exploit the bone marrow, able to reproduce and pass on their break open bones and exploit the bone marrow, Homo erectus and Homo which is rich in protein and fats. favourable alleles / genes to the next which is rich in protein and fats. This would have neanderthalensis. This would have provided a larger generation. provided more energy required to support larger form of energy required to support • (The cost is the time and energy that it takes to brains. As the tools developed for the following Homo habilis larger brains. develop the tool.) The benefits are the hominin species, the ability to access protein and • Idea of simple tool, e.g. Oldowan • Fire used by Homo erectus provided efficiency in using the tools to gain a higher fat rich food resources increased having a positive tools are stone tools that have had adaptive advantage of warmth / nutrient value food, and less time processing feedback on brain development. flakes struck off one side of a social gathering and protection from their food. Homo erectus’s cultural evolution included the pebble. predators at night As the tools developed for the following use of fire which enabled them to cook food and OR OR hominin species, the ability to access protein decreased the risk of food poisoning as well as Tools with flat faces at one end / and fat rich food resources increased having a softening the food allowing for the reduction in the use of fire enabled H. erectus to flakes removed from one side. positive feedback on brain development. size of the molar. To exploit the food that would cook food which decreases the risk Homo erectus encourage the support of a larger brain. of food poisoning and softening the The advantage of using fire allowed the food to • Acheulean tools are stone tools food to increase the access to more be softened and more access to types of food, Fire would have also been able to provide that have had flakes struck off nutrients to support a larger brain. allowing a greater ability to physically digest protection from predators at night which would two sides / tools that are biface foods (mastication). have been another adaptive advantage from the OR with flakes removed from both Homo erectus onwards. fire provides a survival advantage to These provided a selective advantage because it sides. decreased chances of sickness and vulnerability Homo neanderthalensis had a developed H. erectus in making more time • Homo erectus is the first hominin to the environment and predators. language, which is related to the Broca’s and available for e.g. making tools (as that is associated with using fire Wernicke’s area. This would have developed over cooked food provides more energy / • (The cost of speech would have been the time cook food / keep predators away. time in the preceding hominin species, as the less time involved in collecting taken to develop a language.) The benefits that brain expanded. Having a language gave the Homo neanderthalensis food) ideas and information like the best hunting ability to pass on ideas, which would have been • Mousterian tools are stone tools Homo neanderthalensis ground and types of beasts to hunt were more easily transferred with a developed language. an adaptive advantage, as they would be better that have been made from large • Tools made by the Levallois able to hunt together as they could plan hunts and flakes. technique. This technique allows • The benefit of cultural evolution must out- were best to find the prey. OR greater control over the size and weigh the costs and associated risks for the Burying the dead would have been a selective shape of the flake products, but it adaptive advantage to have an effect on the Tools had the sides more worked hominin species. advantage as it would have allowed the Homo and more detail along the edges also indicates a great leap from the neanderthalensis to decrease risk of disease and of the tools, (often made into cognitive requirements of previous • Disadvantage may include discussion of natural of predation. Acheulean technologies. selection / demonstration of higher thinking NCEA Level 3 Biology (91606) 2016 — page 4 of 6
Art in the form of petrolithes would have also short stabbing spears) • Speech / development of language skills been a way to communicate by transfer of OR (in Broca’s and Wernicke’s area of information from generation to generation. expanded brain) allowed for Variety of materials used All of the cultural forms of evolution would have effective co-ordination of activities OR provided adaptive advantages for the hominin (e.g. hunting, tool-making, building species who employed them, allowing them a By Levallois involves very and manufacturing) and the greater chance at surviving and being able to basically the striking of flakes exchange of ideas. reproduce and pass on their favourable alleles to from a prepared core. • Burying the dead would have been the next generation. • Bury the dead shows care / idea a selective advantage, as it would of afterlife. have allowed the Homo • Caves / clothing as shelter neanderthalensis to decrease risk of (naturally occurring places to disease and of predation. shelter from adverse weather • Art would have also been a way to conditions). transmit their ideas / transfer • Speech and language. information from generation to generation. • Art provided the ability to communicate.
Not Achieved Achievement Merit Excellence
NØ = no response N1 = 1 point N2 = 2 points A3 = 3 points A4 = 4 points M5 = 2 points M6 = 3 points E7 = 1 point E8 = 2 points or no relevant (1 point only for each Must include (across 2 hominin (across 3 hominin 1st bullet point must be evidence hominin species) definition species) species) incorporated into discussion NCEA Level 3 Biology (91606) 2016 — page 5 of 6
Q Evidence Achievement Merit Excellence
THREE The Out of Africa model suggests that Describe reasons for dispersal Explain the importance of the environment for Discuss the advantages and disadvantages of Homo sapiens evolved in Africa and then and any benefits gained from the the dispersal of modern humans: taking the various migration routes: spread, replacing hominin populations that dispersal of modern humans: • During the time of dispersal, some areas had • Links the environmental conditions to the had migrated earlier into Europe and east • As the populations of Homo gone through an ice age where the sea level different rates of dispersal between Asia, Asia. Reasons for dispersal include pressure sapiens grew, the pressure on had dropped and the water stored in the polar Australia and Europe: eg The faster coastal on resources and climatic changes. As they resources increased. cap and glaciers provided land bridges routes would have had warmer conditions dispersed, this model suggests that there • By moving, H. sapiens were between some landmasses (e.g. from and a good food supply, while the more was limited gene flow between the able to exploit new resources. Palestine to Eurasia). central Asian route (Georgia) into Europe populations in Africa and the populations in would have had a limited food supply as • Change of environmental • Climatic changes would have influenced Europe and east Asia. This is shown by well as cold conditions for travel. There conditions provides better modern man’s rate of dispersal into Asia and mtDNA analysis that show the populations was no migration directly to the access to new regions and Australia, compared to Europe, because the that developed in Africa to have more Mediterranean region initially. variation in their mtDNA as the have had resources. land bridges caused by glaciations allowed • A later migration into North America longer to accumulate mutations in their Describes climatic changes that the migration along coastal routes through occurred following a glaciation period. mtDNA, while the Homo sapiens that have would have influenced modern Asia and to Australia. Because of sheets of Land bridges across the Bering strait would migrated have interacted with other pre- man’s dispersal into Asia, ice, the central Asian route to Europe was have provided an easy way to cross from existing hominin populations as they Australia and Europe: blocked. Europe through to the North American dispersed further, e.g. Neanderthals. Explain the evidence used to support the Out • E.g. Ice sheets prevented continent. This would have meant water of Africa dispersal model: There is no evidence of Neanderthal migration in some areas, but levels were down during a period of cooling mtDNA in humans but rather in their genes, lowered sea levels forming • The Out of Africa (replacement) theory / glaciation. which can be seen in the genome analysis. land bridges in other areas, maintains that the genes in modern-day Discusses how the admixture could have This means that Europeans and east Asian allowing better access humans all came out of Africa. As humans helped the Homo sapiens to migrate: populations carry Neanderthal alleles in between islands and migrated from Africa, they replaced all other their genetic material. continents. human populations with minimal • From interbreeding with the Neanderthals, (interbreeding events only occurred outside The Homo sapiens populations that Describes the Out of Africa interbreeding. (Admixture). Africa) resulting offspring would have an interbred with Neanderthals would have model: • mtDNA is useful because mitochondrial adaptive advantage caused by having the been similar, as they shared a common • The Out of Africa model DNA does not undergo any recombination HLA gene, as they would be resistant to ancestor / DNA link, and different as they asserts that modern humans events – any changes in mtDNA are the diseases that they would be exposed to by subsequently evolved in different areas / evolved relatively recently in result of (gene) mutation only. mtDNA is migrating out of Africa. Offspring carry came under different selection pressures Africa, migrated into Eurasia, inherited from the mother only and passes this advantage enabling them to further that make them more fit to the environment. and replaced all populations through the maternal (female) line of the disperse into new areas. Regions that harbour a high frequency of which had descended from H. family. Neanderthal alleles are enriched for genes • The Homo sapiens that interbred with erectus. • Genetic analysis shows that African affecting keratin filaments, suggesting that Denisovans were able to adapt to living in • Mitochondria are inherited populations show much greater diversity Neanderthal alleles may have helped higher altitudes, as their blood remained from the mother only than non-African, as would be expected if H. modern humans to adapt to non-African thin due to the EPAS1 gene. The following (mtDNA). sapiens originated in Africa, and migrating environments. This means they would have generations that inherited this gene could populations took only a portion of the gene been better suited to migration in these • Y chromosome is inherited gain access to higher altitude routes the pool with them. areas. from father only. original migrants previously found difficult. • Y chromosome DNA can be used to trace The multi-regional model suggests that NCEA Level 3 Biology (91606) 2016 — page 6 of 6
Homo sapiens developed independently. paternal ancestry to approximately 140 000 During the dispersal the sharing of some Y.A. This is useful because the Y DNA indicates the possibility of chromosome does not recombine with X interbreeding between populations (or chromosome therefore only change by alternatively this was from ancient DNA mutation. source / ancestor). The lack of genetic variation in modern humans is due to relatively recent dispersal from Africa, and likely more than one dispersal event, as well as possibility of interbreeding with other hominin populations on the way. The DNA similarities were selected for, to continue to survive in modern human populations.
Not Achieved Achievement Merit Excellence
NØ = no response or no N1 = 1 point N2 = 2 points A3 = 3 points A4 = 4 points M5 = 1 point M6 = 2 points E7 = 1 point E8 = 2 points relevant evidence
Cut Scores
Not Achieved Achievement Achievement with Merit Achievement with Excellence
0 – 8 9 – 14 15 – 19 20 – 24