Tuesday, June 05, 2018
Nice example of theorigenic blindness
Article on sexual dimorphism in the pop science journal Massive.
Clever and painstaking observation of the fossil record, informed by true expertise and long experience. Spoiled by jumping to the automatic Tedx Evolution conclusion.
The intricate features of his long, smooth shell, or carapace, identify him as K.cushmani. His carapace hid and protected his delicate body – like a shrimp stuffed inside a clam shell – as he propelled himself with scrabbling legs toward the bacteria he fed on. Around him swam hundreds of other ostracods, just like him, though the females were slightly fatter. Unbeknownst to our K. cushmani, this gender difference in body shape – known as sexual dimorphism – marked him and his kind for failure. It turns out that sexual dimorphism correlates extremely well with increased extinction rate, with more than 99 percent of models correlating the two. But it’s not sexual dimorphism itself that’s the problem – it’s the type of sexual dimorphism. Only where males were larger or more elongate than females was the extinction rate higher. In living ostracods, larger or more elongate male carapaces are used to house larger sex organs. So by analogy, for the fossil species, males that invested more resources in reproduction did so at significant evolutionary cost.The usual Tedx logic. Evolution is random mutation selected by energy cost. But the correlation could just as well arise from the opposite causation, which is equally evolutionary. Not ID or creationist! If the ostracods are feeling threatened and stressed by low food supplies or changing ocean conditions, they would try harder to reproduce. The males would display their fitness more dramatically, trying to get more and better females. Obvious analogy: Flowers appear when the plant is stressed. What's the difference between these two evolutionary speculations? The one chosen by the researchers is inorganic and mechanistic, assuming that "random" drives all modifications. The alternate flower-style theory assumes intelligent purpose-driven genes, plus a certain degree of collective intelligence. ¶ 4:17 AM
