The development of an egg cell and its activation in response to encountering a sperm cell exhibit exquisite design, being contingent upon multiple mutually dependent processes, all of which are needed for successful reproduction. When considered in conjunction with the incredible engineering features of the sperm cell and the seminal fluid, it would seem to put the thesis of design almost beyond question.

Several different structural components are necessary for the vertebrate sense of hearing. It strains credulity to suppose that an unguided process of random variation sifted by natural selection could assemble such a delicately arranged system. It instead points to a cause with foresight.

Muscle contraction — which we so easily take for granted — is an incredibly complex and elegant process, involving incredible engineering and design. To contend that the phenomenon of muscle contraction arose through a blind and undirected process, one tiny Darwinian step after the other, seems to me to strain credulity.

Muscle is one of the most fundamental of animal tissues. It is muscles that animate our bodies — allowing us to move, stand upright, breathe, and even speak. Muscles are precisely the sort of thing that we might expect a designer of embodied intelligent beings to produce.

Here, I will address an objection to irreducible complexity I’ve encountered that attempts to handwave the argument away as though I were missing something obvious. This is, in my judgment, one of the weakest objections to irreducible complexity, though it persists as a popular one — even among experts. It is therefore worth commenting on. I will use as case examples two responses to recent articles of mine.

As in the case of so many physiological processes, the male erection and ejaculation reflex requires multiple processes to function in unison to achieve a higher-level objective — in this instance, depositing seminal fluid, containing millions of sperm cells, in the female vaginal cavity.

An important requirement of life is a means of minimally accurate self-replication. Biologist Jack Szostak explains that “In order for RNA to have emerged as the genetic polymer that enabled protocells to evolve in a Darwinian manner, the process of RNA replication must have been accurate enough to allow for the transmission of useful information from generation to generation, indefinitely.”