Natural selection, according to the theory, acts upon genetic variations, favoring those that suit the organism for its environment and culling from the population those which don't. But nothing in the theory explains, or at least explains well, biological extravagance, notwithstanding that we see such extravagance all around us.
An essay at Evolution News discusses three examples of biological phenomena that far exceed anything that would have been necessary for fitness. The three are the Venus Flytrap, the stripes on a zebra, and the prodigious memory capability of the human brain.
Here's what the article says about the Venus Flytrap:
New work by researchers in Germany, published in Current Biology, shows that this plant can count! The team's video, posted on Live Science (see below), shows how the trigger hairs inside the leaves generate action potentials that can be measured by electrical equipment.Here's the video mentioned above: How did such an astonishing ability, not just the ability to capture prey but also the ability to count, ever evolve through blind, purposeless processes in a plant?
Experiments show that the number of action potentials generates different responses. Two action potentials are required to close the trap. When closed, the plant starts producing jasmonic acid.
The third spike activates "touch hormones" that flood the trap with digestive juices. The fifth spike triggers uptake of nutrients. The struggling insect will trigger some 50 action potentials. The more they come, the more the trap squeezes tighter and tighter, as if knowing it has a stronger prey.
The squeezing presses the animal against the digestive juices, also allowing more efficient uptake of nutrients.
"It's not quite plant arithmetic, but it's impressive nonetheless," says Liz Van Volkenburgh of the University of Washington in Seattle. "The Venus flytrap is hardwired to respond in the way that's now being described," she says.
Wayne Fagerberg at the University of New Hampshire in Durham agrees. "Obviously it doesn't have a brain to go 'one, two, three, four'," he says. "Effectively, it's counting. It's just not thinking about it."
In our experience, "hardwired" things that can count and activate responses are designed. This elaborate mechanism, involving multiple responses that activate machines on cue, seems superfluous for survival. The Venus flytrap has photosynthesis; it can make its own food.
The argument that it needs animal food because it lives in nutrient-poor soil is questionable; other plants, including trees, do fine without animal traps.
Regarding the prodigious memory capabilities of the human brain - ten times what neuroscientists had previously estimated and in the same ballpark as the Worldwide Web (!) - one wonders what need is there for such extravagance? How and why would such enormous capacity evolve by chance?
Evolution News comments:
A petabyte is 1015 bytes, or a thousand terabytes — and that’s a conservative estimate. An evolutionist might be able to defend enough memory in a hominid brain to remember dangers from predators and where to find food or a mate, but why this superabundance of capacity?I'm reminded of a quip by philosopher Alvin Plantinga who was discussing the brain's superfluous ability to do higher math and the utter implausibility of such an ability being explained by a process that merely suits human brains for reproductive success.
It’s also efficiently stored, searchable, and quickly accessible. It is so good, in fact, that computer engineers want to imitate its “design principle” to reach that kind of incredible power and energy efficiency.
Plantinga observed dryly that, after all, it's only the rare graduate student whose prospects for reproductive success are enhanced by his ability to solve differential equations.
