See my responses below to each of your questions. Yes, of course, you may use our notes in future communications. Remember it's my goal to help you better understand the theory of evolution by means of natural selection.
A. Berta
1. What are the links between microevoltion and macroevolution, if there are any?
Let's begin by defining terms ---microevolution is change in gene frequency in a population and macroevolution is evolutionary change above the species level. Macroevolution is taking place by the same process as microslection ---natural selection and adpatation.
Now let's consider an example of macroevolution-the transition from reptiles to mammals. Mammals evolved from reptiles in a series of small changes over a long period of time. The characters that can be most clearly reconstructed in fossils are those concerned with feeding and locomotion, because those are related to preserved bones and teeth. The origin of mammals can be traced through a series of reptilian groups called mammal-like reptiles. The evolution of mammal-like reptiles proceeded in 3 main phasess:
1) pelycosaurs (lived 300 mya) differered form their reptilian contemporaries in having an opening in the cheek region through which a muscle passes (in living animals). These muscles acted to close the jaw and is the first sign of of the more powerful jaw of mammals.
2) The second phases of mammal-like reptile evolution belonged to therapsids. They show an opening in the cheek region of the skull larger than pelycosaurs and they show the first signs of holding their legs upright. A little later a group within therapsids gave rise to the
3) third and final phase, the cynodonts. Cynodont jaws resemble mammalian jaws more closely and their teeth are more complex (multicusped). Thus, the fossil record for the origin of mammals shows the gradual changes from reptilian to mammalian characters and that these differences between reptiles and mammals concern adaptations. (ie. locomotory adaptations for rapid movement (upright vs. sprawling posture) and powerful and efficient feeding (mammlian teeth and powerful jaws)). These adaptive changes were brought about by natural selection.
2. Most evolutionist believe that the beginning of this cylce started with a big bang and will in with a "big squish" and then restart the cycle. my question is where did all the matter come from in order for this cycle to exist?
Science can make no statement about the nature of the Universe prior to that explosion, because the physics of the Big Bang is not fully understood. We know that space, time, matter and energy existied after the Big Bang (Einstein's theory of relativity)
3. Macroevolution is based on billions and billions of years. Science is the observation, hypothesis, experiment, and conclusion or more observations. How can we observe macroevoltion considering that Evolution Theory has not even been around for a 1,000 years? How do we know that the earth is billions of years old?
In fact the earth is approximately 4.5 billion years old. The dating of radioactive isotopes in the oldest rocks has confirmed this (read Chap 20 : 380-382 in Purves). The oldest forms of life have been identified from rocks approx. 3.8 mya. Evidence for life is seen in cells that show evidence of cell division (reproduction).
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