A plant species found in the area immediately around Sydney has also been found in a small area in the Gibraltar Range in the far north of NSW. Predict what might happen to the TWO populations over the next 5 million years, in terms of Darwin/Wallace's theory of evolution. (3 marks)
BIOLOGY, M3 2010 HSC 30
Geological and biological history of New Zealand
Use this information and other relevant knowledge to demonstrate how the practice of biology has led to the validation of current theories of evolution. (7 marks)
--- 18 WORK AREA LINES (style=lined) ---
→ In the New Zealand information, many practices of biology were undertaken to compile the data.
→ The observations of fauna in New Zealand represent an important practice in biological science. Making clear, dispassionate and unbiased observations, and recording such observations are intrinsic to science and provide an essential pathway to validating theories.
→ These observations validated the idea of convergent evolution; birds in New Zealand, without competition from mammals, developed similar characteristics and were able to live in the same environments as mammals do elsewhere.
→ Practices in palaeontology of ageing fossils by radiometric dating or stratigraphy, describing fossils and comparing fossils, allows a history of fauna of New Zealand to be compiled, and history of islands (eg. deducing from fossils found to be almost completely marine that New Zealand was covered by oceans).
→ The history of fauna and geologic events validates Charles Darwin’s theory of evolution in that populations of birds, which began as occasional visitors, gradually changed into permanent endemic species.
→ Divergent evolution is validated as new unique species develop from migratory species, as shown by the fossils of new, unique birds.
→ The data also validates the punctuated equilibrium theory in that the diversification of bird species happened very quickly in the space of only 2 million years.
BIOLOGY, M3 2014 HSC 26
Explain how Darwin/Wallace's theory of evolution by natural selection and isolation accounts for convergent evolution. Use an example to support your answer. (5 marks)
→ Convergent evolution occurs when two species evolve to possess similar characteristics by natural selection in similar environments.
→ The organisms cannot interbreed to share any new DNA generated by mutation: they are genetically isolated from each other yet they develop similar characteristics.
→ When variation exists in a population, the theory of evolution by natural selection states that this variation will cause some individuals to be better suited to their environment. In this way, they are more likely to survive and hence reproduce, passing on their adaptive characteristics to further generations. After many generations, the traits of those variants are common in the population.
→ Dolphins and sharks demonstrate convergent evolution. The dolphin is a mammal and the shark is a fish. They inhabit the marine environment which imposes the same selection pressures on both types of organism.
→ Despite being genetically isolated, they both exhibit a streamlined body shape and possess fins for propulsion and stability.
→ These features are adaptive for movement in a highly viscous environment.
→ Convergent evolution occurs when two species evolve to possess similar characteristics by natural selection in similar environments.
→ The organisms cannot interbreed to share any new DNA generated by mutation: they are genetically isolated from each other yet they develop similar characteristics.
→ When variation exists in a population, the theory of evolution by natural selection states that this variation will cause some individuals to be better suited to their environment. In this way, they are more likely to survive and hence reproduce, passing on their adaptive characteristics to further generations. After many generations, the traits of those variants are common in the population.
→ Dolphins and sharks demonstrate convergent evolution. The dolphin is a mammal and the shark is a fish. They inhabit the marine environment which imposes the same selection pressures on both types of organism.
→ Despite being genetically isolated, they both exhibit a streamlined body shape and possess fins for propulsion and stability.
→ These features are adaptive for movement in a highly viscous environment.