Unpredecented Global Heat Left Footprints in Teeth

Global warming of epic proportions is now suggested not only as a major cause of the end-Permian mass extinction but also as the explanation for a five-million-year evolutionary lag in recovery of biological diversity. The Permian graveyard, conventionally dated at about 250 million years ago, marks the final appearance for more species than any other catastrophe in history, exceeding even the end-Cretaceous dinosaur swan song.

Researchers reported October 19 in Science that they have developed a way to precisely measure temperatures during the Permian-Triassic transition. They extrapolated temperatures from oxygen isotope ratios in 15,000 tiny conodont teeth. Conodonts are extinct eel-like marine vertebrates found in the fossil record from the Cambrian through the Triassic layers. The teeth were removed from two tons of South China rock from the Permian-Triassic boundary, with dates ranging 252 to 247 million years ago. Because marine animals today preferentially utilize lighter isotopes of oxygen in their skeletal construction at warm temperatures, the oxygen isotope ratio was used to estimate the temperatures at which the teeth were built and buried.

The idea of high temperatures associated with the Permian mass extinction is not new.

The idea of high temperatures associated with the Permian mass extinction is not new. The end-Permian rock layers coincide with enormous quantities of Siberian volcanic lavas, so some have suggested that carbon dioxide gas released with those eruptions caused severe global warming.1 Those Siberian volcanic lavas cover an area nearly the size of Australia.2

“Global warming has long been linked to the end-Permian mass extinction, but this study is the first to show extreme temperatures kept life from re-starting in Equatorial latitudes for millions of years,” according to lead author Yadong Sun. Hot conditions persisted for 5 million years, the authors conclude, due to the massive deficit of plant life. Without plants to remove carbon dioxide from the atmosphere, the earth became “like a runaway greenhouse,” coauthor Paul Wignall explains, producing temperatures too hot for most organisms to thrive or even survive. Based on isotopes in conodont teeth, researchers believe temperatures at the ocean surface exceeded 40 degrees Celsius (104 degrees Fahrenheit). (Normal equatorial sea-surface temperatures today are 25 to 30 degrees Celsius (77–86 degrees Fahrenheit).3

The dates associated with the current study’s time-tracked temperatures are based on unverifiable assumptions associated with dating methods. Those geologic layers of sediment that were deposited by the Flood and its aftermath were laid down over a short span of time, not millions of years. The fossil record is not a chronicle of gradual evolution and extinction. Much of the fossil record reflects instead the order in which organisms were catastrophically buried during the global Flood.

The global Flood began with the disruption of the ocean basins as “the fountains of the great deep were broken up” (Genesis 7:11). The Paleozoic rock sequence consists of the lowest layers deposited by the Flood. Marine creatures buried by the initial oceanic upheavals dominate it. In the uppermost Paleozoic rocks, amphibians and land animals make their appearance. The “mass extinctions” in the fossil record are really regions representing the massive burial of organisms swept together from various ecosystems.4 Thus the Permian layers at the top of the Paleozoic sequence likely correspond to the time when rising Flood waters were beginning to overwhelm more terrestrial ecosystems.5

The likelihood that hot temperatures prevailed when Permian and Early Triassic sediments were deposited also makes sense in light of biblical history. Geology reveals much volcanic activity associated with the fossil record, notably in the end-Permian and end-Cretaceous layers. That high temperatures prevailed when they were deposited is consistent with the unprecedented level of volcanic activity associated with the global Flood. The break up of oceanic crust would have released tremendous quantities of hot lava into the oceans. However, those remarkably hot conditions did not produce five million years of scorched earth. But the effects of this volcanic heat did continue past the year of the global Flood, promoting meteorological conditions that within a few centuries ultimately produced the Ice Age.