Young Earth Creationists are a Christian fundamentalist subset who dismiss any evidence for a universe older than a few thousand years. They also hold a literal interpretation of Genesis, meaning they think Earth was completely covered by water following a flood that would have dwarfed any that a Hollywood blockbuster could muster. Much evidence works against the idea of worldwide flood 4,400 years ago, but our limited focus here centers on ecology.

In the flood fable, Noah brought animals aboard his ark in pairs or septets. To get around the sizable obstacle of about 50 million critters fitting onto a ship the size of 1.5 football fields, YECs fabricated then notion of “kind,” which they never define or quantify. From each “kind,” thousands of different species are said to have emerged. To YECs, this does not count as evolution since there is no change from one kind to another. They reluctantly allow for incremental, minor adaptations and will allow that a squirrel’s fur may change to a more advantageous color. However, the bushy-tailed rodent could not have a prehistoric horned gopher as its ancestor from 100 million generations ago.

This is a desperate, ad hoc hypothesis to try and get around scientists literally observing evolution in action, such as with Richard Lenski’s ongoing e. coli experiment or with the Florida lizard that was seen developing a toe pad to escape an invasive species. This raises another issue, as to why an organism would need to adapt at all if it and its surroundings were created by an infallible designer, but perhaps that’s for another post.

A “kind” is very roughly analogous to the biological grouping of Family. The only criteria for which animals belong in each “kind” seems to be similar appearance. For example, a horse, zebra, and donkey would be in the same kind, but a horse, opossum, and turtle would not.

According to retired geology professor and Skeptical Inquirer contributor Lorence Collins, there are up to 50 million species today, and many more times that of cousin species that have gone extinct.

YECs think fossils of both extinct and extant species were buried in sedimentary rocks deposited by the great flood. YECs further believe that all these creatures were created at the same time. Yet all known sea reptiles, such as ichthyosaurs and plesiosaurs, are found in fossils from the Eocene Epoch, while those layers feature no such fossils from sea-living cetaceans like dolphins, whales, and porpoises. Those extinct sea reptiles filled the same ecological niche that cetaceans do today and both groups swam in the same locations. Yet a YEC will insist that all cetaceans survived the flood but not a single sea reptile did. For this to be true, cetaceans and sea reptiles occupying the same parts of the ocean would have to have been completely segregated by the flood, which then killed all sea reptiles and spared the cetaceans.

The truth, Collins wrote, is that sea reptiles went extinct well before mammals began adapting to ocean life and became ancestors of today’s cetaceans. The geologic column and distribution of sea reptile and cetacean fossils bear this out.

We now leave the sea for the sky but encounter the same problems with Young Earth Creationism. There are about 9,500 species of birds on Earth today and an additional 10,000 extinct bird species that have been found in sedimentary rocks, which were deposited 4,400 years ago in the YEC narrative.

Young Earth Creationist Jean Lightner suggests that aboard the ark were 196 pairs of bird “kinds,” which evolved into 10,000 extinct species and 9,500 living ones. This is an instance of special pleading, as a group that mostly rejects random mutation and natural selection will, out of extreme convenience, adopt a hyper version of evolution in order to make their timeline work. But to produce the 19,500 species of birds from 196 pairs in 4,400 years would require evolution taking place exponentially faster than what any observation of genetic change has indicated is possible.

Now onto land animals and more deficiencies in the YEC model. YECs would presumably consider elephants, mastodons, and woolly mammoths to be in one “kind,” distant cousins descended from a pair of lumbering beasts who took up the Ark’s trunk space.

However, about 10,000 fossils of extinct elephant relatives have been found from Africa to Iraq, and millions of mammoth fossils have been unearthed in Siberia. Consider how long it takes elephants to reproduce. They have a 22-month gestation period, some species only begin to procreate at age 20, and they will have offspring only about every five years. These are fatal blows to the notion that hundreds of species totaling millions of mammoths, mastodons, and elephants came into existence and were dispersed over thousands of miles in a period lasting barely 2,000 years.

Meanwhile, there are about 35 extant and 150 extinct feline species, which YECs say all came from a pair that boarded the ark, a cat walk if you will. But again, there would be inadequate genetic diversity to allow for this much branching of a species tree in 4,000 years, which is the blink of an evolutionary eye. There are similar examples among rhinos, canines, and bears. The number of extant and extinct members could not be crammed into such a short time period. There would be too few years to reproduce and have descendants evolve into this many different species.  

YECs face another insurmountable obstacle with plants. In China, fern fossils have been found in ash sandwiched between two coal layers. Per Collins, this is the result of volcano millions of moons ago that sent hot ash spewing and killed all plant life in the affected area. As it turns out, volcanic ash is excellent at preserving plant fossils and these highly delicate leaves were sustained when surrounded and covered by these fiery remains.  By contrast, if the plants’ leaves had been deposited in sediments that were transported by rushing water that had fallen at a rate of 360 inches an hour – 25 times faster than any recorded deluge – they would have been torn apart and mixed with fragments of different plant types.