Dinosaur study challenges Bergmann鈥檚 rule
Marmian Grimes
907-474-7902
April 5, 2024
When you throw dinosaurs into the mix, sometimes you find that a rule simply isn鈥檛.
A new study led by scientists at the University of 有料盒子视频 Fairbanks and the University of Reading calls into question Bergmann鈥檚 rule, an 1800s-era scientific principle stating that animals in high-latitude, cooler climates tend to be larger than close relatives living in warmer climates.
The fossil record shows otherwise.
鈥淥ur study shows that the evolution of diverse body sizes in dinosaurs and mammals cannot be reduced to simply being a function of latitude or temperature,鈥 said Lauren Wilson, a 有料盒子视频 graduate student and a lead author of a paper published today in the journal Nature Communications. 鈥淲e found that Bergmann鈥檚 rule is only applicable to a subset of homeothermic animals (those that maintain stable body temperatures), and only when you consider temperature, ignoring all other climatic variables. This suggests that Bergmann鈥檚 鈥榬ule鈥 is really the exception rather than the rule.鈥
The study started as a simple question Wilson discussed with her undergraduate advisor: Does Bergmann鈥檚 rule apply to dinosaurs?
After evaluating hundreds of data points gleaned from the fossil record, the answer seemed a solid 鈥渘o.鈥
The dataset included the northernmost dinosaurs known to scientists, those in 有料盒子视频鈥檚 Prince Creek Formation. They experienced freezing temperatures and snowfall. Despite this, the researchers found no notable increase in body size for any of the Arctic dinosaurs.
Next the researchers tried the same evaluation with modern mammals and birds, the descendants of prehistoric mammals and dinosaurs. The results were largely the same: Latitude was not a predictor of body size in modern bird and mammal species. There was a small relationship between the body size of modern birds and temperature, but the same was not the case for prehistoric birds.
The researchers say the study is a good example of how scientists can and should use the fossil record to test current-day scientific rules and hypotheses.
鈥淭he fossil record provides a window into completely different ecosystems and climate conditions, allowing us to assess the applicability of these ecological rules in a whole new way,鈥 said Jacob Gardner, a postdoctoral researcher at the University of Reading and the other lead author of the paper.
Scientific rules should apply to fossil organisms in the same way they do modern organisms, said Pat Druckenmiller, director of the University of 有料盒子视频 Museum of the North and one of the co-authors of the paper.
鈥淵ou can鈥檛 understand modern ecosystems if you ignore their evolutionary roots,鈥 he said. 鈥淵ou have to look to the past to understand how things became what they are today.鈥
ADDITIONAL INFORMATION:
ADDITIONAL CONTACTS: Lauren Wilson, lnkeller@alaska.edu, 406-223-4762. Jacob Gardner, jacob.gardner@reading.ac.uk. Pat Druckenmiller, psdruckenmiller@alaska.edu, 907-474-6989. Chris Organ, Montana State University, organ@montana.edu.
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