"The success of Darwinism was accompanied by a decline in scientific integrity.
This situation, where scientific men rally to the defence of a doctrine they are unable to define scientifically, much less demonstrate with scientific rigour, attempting to maintain its credit with the public by the suppression of criticism and the elimination of difficulties, is abnormal and undesirable in science." - Professor W. R. Thompson, Introduction to the 1956 reprint of 'The Origin of Species: The Preservation of Favored Races in the Struggle for Life'
My end of the affair with Darwinism, especially evolution, was the increased knowledge of paleontology, with myriad quantum leaps in organismic complexity achieved through the almost Lamarkian coalescence of multiple major advances simultaneously in some hypothetical ancestral stock. As a matter of probability, the odds are staggeringly large against even one such transition, yet we were to believe that numerous such transitions had been made on the lengthy journey from coacervate molecules to
Homo sapiens.
While, admittedly, transitional forms would be theoretically of short duration and scarce in the fossil record, they continue to be absent, dependent on such things as neotenic tunicate larvae on the way to
amphioxis.
But Darwinism had the tremendous benefit as a mindset, allowing for the classification of some forms, even of our own species, as "primitive", evidenced by differing levels of technological development which contributed* to a lack of time to spend pondering in omphaloskepsis vs grubbing up the resources necessary for survival, and as such, something to be exploited more as a resource than treated as human, and whose unrecognized natural resources were fair game.
This played into the Europe of the Enlightenment, being the only thing needed to justify an era of colonialism to any who might have had qualms about looting resources, but even better, giving less than human status to any group justified in the minds of many acts which were every bit as savage as the behaviour of those who were dubbed thus, mindset which persists to this day among any groups who consider themselves superior to others without just cause. I must note that those who conduct themselves in this way consider themselves superior through intellectual, economic, or even genetic circumstance, and as such, all others are lesser, and fair to subject to any and all depredations. (Consider those "elites" who would have us all eat bugs or artificial protein while they eat real meat.)
(*This is a chicken/egg problem. Lack of technology fosters a lack of time and energy to develop technology; survival comes first. Without abundant resources, time is spent gathering needed resources. With technology, resources can be multiplied, granting additional time to develop more technology, but the time to develop technology simply may not be available for small groups, thus their level of technological development remains low.)