A global shift towards warmer temperatures could mean a far-away future of horse-sized snakes and snake-sized horses, NBC News reported.

Many millions of years ago, when the earth was warmer, that was the case: large reptiles and small mammals.

"You see the size of these animals dancing with the climate," said Jonathan Bloch, a paleontologist at the Florida Museum of Natural History.

At the 2013 Science Writers Conference in Gainesville, FL, a 5-day "mix of professional development workshops, briefings on the latest scientific research, extensive networking opportunities, and field trips," Bloch spoke on Monday about a particular balmy point in earth's history known as Paleocene-Eocene Thermal Maximum (PETM), NBC News reported.

Because of the natural emission of greenhouse gases, temperatures during this period soarded 9 to 13 degrees Fahrenheit warmer, including an average of 93 degrees Fahrenheit in areas containing the giant snake, Titanoboa.

The Paleocene era began around 65 million years ago as dinosaurs were becoming extinct and lasted until around 56 million years ago, at which point the Eocene epoch began, NBC News reported. The period known as PETM occurred when the two ages crossed and lasted around 160,000 years.

The best site for Paleocene-Eocene fossil finds is the Cerrejon Mine in Colombia, appropriate because it has "coal seams so active they can spontaneously combust," according to NBC News.

"It really is like hell, but it's heaven for fossils," Bloch said.

Exploring the Cerrejon Mines, Bloch and his team found evidence of a giant turtle ("the size of a kitchen table") and a snake so enormous it "would have to squeeze through the door, and come up to your waist," Bloch said.

Because reptiles are ectoderms, or cold-blooded, and rely on the environment to regulate their body temperatures, a hotter climate promotes their growth, Bloch said.

Recent research published Nov. 1 supported Bloch's assertion that warm temperatures miniaturize mammals, though the study didn't as thoroughly examine the enlarging effect on reptiles, according to the press release. University of Michigan Paleontologist Phillip Gingerich and colleagues found a separate global warming occurrence two million years after the end of PETM. The time period, dubbed "ETM2" supported horses the sizes of dogs.

"The fact that it happened twice significantly increases our confidence that we're seeing cause and effect, that one interesting response to global warming in the past was a substantial decrease in body size in mammalian species," Gingerich said.

The collective research could help scientists better understand the rise of mammals, according to Bloch.

With today's greenhouse gases at levels not seen since over 10 million years ago, the work of Bloch, Gingerich, and others could also add to climate change research, NBC News reported.