Cavemen loved the taste of fish and chips.
Humans have long had a taste for fish and chips
Experts have found that Neanderthals and cavemen possessed the same gene that makes modern humans crave carbohydrates like potatoes.
The AMY1 gene speeds up sugar digestion with an enzyme in saliva called amylase and allowed our ancestors to gorge on starchy food.
It could explain why Brits prefer starch-heavy dishes such as fish and chips.
Dr. Omer Gokcumen, study author from the University of Buffalo in New York, said: "The more amylase genes you have, the more starch you can digest.
"This allowed humans to adapt to shifting diets as starch consumption rose dramatically with new technologies and lifestyles."
Analysis of human remains found that the AMY1 gene started in Neanderthals approximately 800,000 years ago before flourishing as modern humans developed further copies with a varied diet.
Dr. Gokcumen said: "People with higher AMY1 copy numbers were likely digesting starch more efficiently and having more children.
"Their lineages ultimately fared better over a long evolutionary timeframe."