Diets shaped chameleon heads, according to Science (AAAS) News 31 March 2017 and Functional Ecology vol. 31, pp 671–684, March 2017, doi: 10.1111/1365-2435.12750.
A group of scientists studying a genus of South African dwarf chameleons named Bradypodion were intrigued by the variety of head shapes within the same genus – some tall, some wide and some with crests and frills. They studied the head shapes of 14 different species of lizards, examined what they ate, and measured how much bite force they could generate. They found forest dwellers had taller heads and ate soft food such as butterflies, dragonflies or small reptiles. Those with crests had stronger bites and could eat larger insects. The plains dwelling chameleons had wide mouths, but lacked crests and tended to eat small beetles.
The title of their report is “Does diet drive the evolution of head shape and bite force in chameleons of the genus Bradypodion?” The research team answers this question in the summary of their study: “These data suggest that the cranial system in chameleons of the genus Bradypodion evolves under natural selection for the ability to eat large or hard prey”.
In a reference to another genus of living things whose diet is claimed to drive its evolution, the Science News article is entitled: “Darwin’s finches have nothing on these chameleons”. Science
Editorial Comment: Our answer to the scientists’ question “Does diet drive the evolution of head shape and bite force in chameleons?” is NO! Diet never drives evolution, because trying to eat what an animal’s head and mouth can’t bite will not change its genes to produce new features.
A much better explanation of these observations of chameleon heads and chameleon diets is that chameleons that already have strong enough jaws to crunch beetles survived in places where beetles are the most abundant food, and those with less powerful bites did well in places where softer prey was available, but could not survive where soft foods were not available.
The Science News article is right to make a parallel between Darwin’s finches and chameleons, because, in spite of being held up as an icon of evolution, the finches have not evolved either. Galapagos finches eat whatever their beak shape will allow them to eat. If they don’t find the appropriate food they die out, leaving those whose beaks could pick up whatever food was available to survive and reproduce. In both cases, chameleons and finches, natural selection has been at work, but neither creature has evolved.
Chameleon heads and finch beaks are better explained by starting with Genesis, which tells us God made the original finches and chameleons as fully formed creatures in separate kinds. Having an original “kind” does not mean all individuals were identical – there is, and was, inbuilt variation within each kind, depending on how many individuals were created in that kind. After Noah’s Flood the environment degenerated, and extremes of climate meant greater regional differences in vegetation. Some animals had to take to catching prey to survive, rather than eating plants as they were originally created to do. Natural selection would have separated out the various head and beak shapes by enabling creatures already equipped with appropriate variations to survive, while those with other variations died out or found somewhere else to live.
Those who want to claim God used evolution by natural selection to create, need to understand that natural selection only works by eliminating the unfit, and is the result of degeneration due to human sin and God’s judgement after creation was complete. Natural selection is a real process, but it is actually a constant reminder that the world is going downhill from a very good beginning, not evolving upwards.
Evidence News vol. 17, No. 6
19 April 2017
Creation Research Australia
Were you helped by this item? If so, consider making a donation so we can keep adding more items. For USA tax deductible donations click here. For UK tax deductible donations click here. For Australia and rest of world click here.