Enough with personification. Nature isn't a person, so it never had thoughts or ideas. But, to get to the point, macroevolution has fizzled, apparently. There was only one Cambrian explosion event. Nature never again had a period where so much diversity and complexity in life came about so rapidly. Not only that, but life seems to have gotten stuck in ruts. There are only about 52 phyla (major body types of life forms) of plants and animals and that number hasn't been growing for millions of years, as best I can tell. Some people believe these body plans are fixed and no amount of evolution can change these body plans.
One could argue that evolution is taking a temporary "break" and will accelerate at some future point. However, the slow down in macroevolution started hundreds of millions of years ago. Evolutionists believe that for some 2.5 billion years evolution was moving extremely slowly. Then, at around 580 to 530 Ma, evolution accelerated rapidly. From about 400 Ma till today, macroevolution has been slower, and I argue that it has been slowing down. (Microevolution seems just as quick as ever.) So, what's the deal? Why should this be happening?
Evolution now seems to consist almost exclusively of rapid microevolution (changes within a species). There are few examples of new species forming. In fact, the rate of speciation is so low that species are going extinct much faster than they are being formed by evolution. At the current rate, life would go extinct relatively quickly, with or without a new asteroid striking the earth. How can naturalistic evolution explain these things? The fact that microevolution is so fast and microevolution is thought to lead to macroevolution, should mean that speciation can happen rapidly, but we don't see that taking place. (It is doubtful that humans are causing all these extinctions, since the slow down in evolution seems to date to much earlier periods before Homo sapiens rose to prominence in the world.) It seems that nature has had only a finite set of designs to work with. Eyes, ears, legs, mouths, gills, feathers . . . As time has gone by, original designs have become more and more rare.
From the pure evidence, one could argue that species have become more fixed and less capable of major changes. If evolutionary creationism is true as explained on this blog, then it is quite reasonable that macroevolution has come to a stand still, and animals now produce each "after their kind" as the Bible says. There is little to no new genetic information left to allow for major new body part designs to develop. Sure, nature can still rearrange current information and change the size, shape, and color of body parts, in some cases, but you will never see a new type of advanced eye growing on an animal or any other design that requires new genetic information. Over time, unused genetic information within animals and plants was discarded, with some animals or plants more quickly trashing unused sequences and others holding onto the unused sequences for possibly hundreds of millions of years.
During times when there were fewer species and competition was less fierce, according to this theory, evolution could progress much quicker. Most minor changes are problematic, so intensified competition tends to weed out most changes. Competition has not been the driving force behind evolutionary changes. Evolution is smart and designed and efficient. Therefore, during times when competition was not as fierce and genetic reorganization and new expression could occur more freely without the need for great efficiency initially, evolution was able to occur more rapidly and march towards new designs (though not necessarily better designs). This fits the evidence found in the fossil record. After extinction events, there was often rapid speciation. New designs proliferated during such periods of time. "Survival of the fittest" can't completely account for these changes in rates of speciation, in my opinion.