"Exposing Discovery Institute": video series by "Professor" Dave Farina

The problem with genetic drift, recombination, horizontal gene transfer and the other alternate ways genetic variations come about cited by Farina is that they all are (like mutations themselves) random with respect to fitness and therefore subject to the same severe limitations in terms of what they can accomplish (in conjunction with natural selection). They are just as totally impotent as mutations in being able to build innovative new irreducibly complex biological systems.  

Random genetic variations plus natural selection can build various types of finch beaks. This is called microevolution. But this is totally incapable of inventing and building the basic design of the beak itself along with all the associated intricately interacting organ systems of the bird - this last is called macroevolution, and is totally out of reach of RM + NS. Sexual selection certainly isn't random and is in the direction of a kind of fitness, but all it can do is what RM + NS can only do, which is modify existing biological structures a little. Sexual selection, like random genetic variations, is totally incapable of inventing and building innovative new irreducibly complex living systems. It can make a new variation on the ingenious tail feather design, but it can't invent the basic design of the feather itself along with all the supporting organ systems that have to go with it.

So, by citing the significant number of random modes of genetic variation that have been found by researchers, Farina is not even addressing the severe problem he is confronted with - explaining the sudden origin of complex novel new biological systems, for instance the sudden (in evolutionary terms) appearance of more than twenty new animal body plans and phyla in the Cambrian explosion, with the major body plans like the arthropods and vertebrates having extremely complex irreducibly complex body subsystems such as skeleton, nervous system, brain, sensory system including eyes, digestive system, musculature, it goes on. 

Niche construction is just another way microevolution takes place and can't in the slightest explain macroevolution. 

Epigenetics is another matter. Apparently this may be a means of genetic variation that allows living organisms to modify their own genome in order to adapt to changing conditions. It may in truth be another way beside RM + NS that microevolution takes place. But some biologists who are trying to break with Darwin but still avoid Intelligent Design have suggested that this is the way novel new organ systems and other macroevolutionary developments in evolution happen - not by outside intelligent intervention in evolution, but by some sort of semi-intelligent inner directedness present in all life including single celled organisms. I myself don't find this credible, because inventing irreducibly complex biological machines inherently requires conscious intelligent agent(s) capable of thought and foresight, and it is incredible to suggest that nonhuman animals and plants to say nothing of single celled organisms have such capability.

It is frankly a bit amazing and absurd the lengths to which staunch gradualist evolutionists will go to avoid the need for an intelligent designer ~ of any nature. The more I look at them, the more they just appear as Atheists who feel an automatic unease at intelligence and design in life ~ anyone who believes in such ideas must all be secretly closet Christian Creationists. The strawmanning is so tiring to deal with. Frankly, at some point I just gave up debating with them, along with internet Physicalists and Materialists, because it does not matter what you say ~ you always get the same braindead replies that always strawman your position invariably.