Each question write about 200-250 words count.
- In the class material we make use of the Drake equation as providing a statistical estimate of the number of civilizations that might currently exist in our Galaxy and are capable of communication. Recently, however, some scientists have argued that the Drake equation is an inaccurate description. This new theory is known as the “Rare Earth Theory” (by Ward and Brownless). Do some research on this new theory and identify what the key components of this theory are that suggests planets like the Earth are much rarer than we think they are.
- Provide a set of arguments for why it is more likely that Life on the Earth originated in the deep ocean thermal vent environment compared to surface ocean processes.
- As many of you heard, or saw the movie, the extinction of the dinosaurs 65 million years ago was thought to be the result of an asteroid impact. Since so many people are saying this it must be true. So, a) find out and report on how secure you think the evidence is that indeed an asteroid did strike the Earth and b) if this impact occurred how, in fact, did it cause a mass-extinction. In other words, what was the mechanism that extincted both ends of the food chain (e.g. the dinosaurs became extinct but so did most forms of ocean plankton). Something more than just blocking out the sun with some dust in the atmosphere must have occurred.
- The evolution of prokaryotes to eukaryotes remains uncertain as does the earliest time at which eukaryotes start to appear in the oceans. The text discusses the proces of endosymbiosis as the most like one that started this evolution but this still largely remains a guess. Research and report on alternative theories to endosymbiosis to account for appearance of eukaryotic cells and also research the lastest findings on when they first start appearing.
- Our Galaxy appears to be long overdue for the occurrence of another Supernova. Find some information on Supernova rates for galaxies like ours and report those results. When was the last Supernova to occur in our galaxy? Based on the supernova rate, do you think that our Galaxy has been deficient in the production of supernova over the last few hundred years?