Describe the three types of selection: directional, stabilizing and disruptive and give an example of each

A directional selection is a mode of natural selection in which a single phenotype is favored, causing the allele frequency to continuously shift in one direction. Under directional selection, the advantageous allele increase in frequency independently of its dominance relative to other alleles; that is, even if the advantageous allele is recessive, it will eventually become fixed. It stands in contrast to balancing selection where selection may favor multiple alleles, and is the same as purifying selection which removes deleterious mutations from a population. For example smaller individuals and will, if the character is inherited, produce a decrease in average body size. 

A stabilizing selection is a type of natural selection in which genetic diversity decreases as the population stabilizes on a particular trait value. Stabilizing selection commonly uses negative selection to select against extreme values of the character. A example of this is human birth weight. Babies of low weight lose heat more quickly and get ill from infectious disease more easily, whereas babies of large body weight are more difficult to deliver through the pelvis.

A disruptive selection is changes in population genetics in which extreme values for a trait are favored over intermediate values. The variance of the trait increases and the population is divided into two distinct groups. The evolutionary process is believed to be the driving force behind sympatric speciation. For example if rabbits were put into an area that had very dark black rocks as well as very white colored stone, the rabbits with black fur would be able to hide from predators amongst the black rocks and the white furred rabbits would be able to hide in the white rocks, but the gray furred rabbits would stand out in both of the habitats and would suffer greater predation.

Explain what microevolution is? What are the three ways that variation occurs?

Microevolution refers to any evolutionary change below the level of species. It also refers to changes in the frequency within a population or a species of its alleles (alternative genes). Mutations alter the order of bases in the nucleotides of DNA. Mutations are likely to be rare and most mutations are probably harmful, but in some instances the new alleles can be favored by natural selection independent assortment (recombination of chromosomes that occurs during sexual reproduction) and the Crossing over that happens during meiosis.

Why is fossil record hard to interpret?

Ever since and before Darwin's time, evolutionists have repeatedly insisted that all species of life have descended from a common ancestor as a result of a purely natural process of adaption to changing circumstances. So in lieu of the existence of any present proof for evolution, Darwin said that the only evidence of it would come from examining the fossil record. Thus if evolution did occur, one would expect to find a gradual series of fossils embedded in the rocks, from simple "almost life" chemicals,  to one-celled creatures, then two-celled creatures, on and on with greater complexity until you have the sponges and algae, the chordates and the trilobites and all of the invertebrates, then the vertebrates appearing animals with backbones, these last including fish, amphibians, reptiles, and man. That is only the Animal Kingdom; there is still the Plant Kingdom to be considered, with grapes and giant sequoia trees, carrots and flowers, potatoes and lawn grass, all of which supposedly evolved from the same common ancestor, according to evolutionists. Darwin stated that many of the great scientists of his time held the fossil record up as evidence against evolution, not for it.

Why evolution is a theory?

The theory of evolution was developed by Charles Darwin, an amateur English naturalist, in the 19th century. He proposed that all of the millions of species of organisms present today, including humans, evolved slowly over billions of years, from a common ancestor by way of natural selection. This idea said that the individuals best adapted to their habitat passed on their traits to their offspring. Over time these advantageous qualities accumulated and transformed the individual into a species entirely different from its ancestors. Darwin's general theory presumes the development of life from non-life and stresses a purely naturalistic (undirected) "descent with modification". That is, complex creatures evolve from more simplistic ancestors naturally over time. In a nutshell, as random genetic mutations occur within an organism's genetic code, the beneficial mutations are preserved because they aid survival - a process known as "natural selection." These beneficial mutations are passed on to the next generation.