DNA changes associated with growth affect the mortality of bigger or taller animals and people. Researchers found the link between taller people and animals and short lifespan.

Researchers from the Norwegian University of Science and Technology's Centre of Biodiversity Dynamics and University of Glasgow's Institute of Biodiversity, Animal Health And Comparative Medicine analyzed how DNA changes affect the lifespan and aging process of wild house sparrows as animals continue to increase in size.

All animals, including humans, possess telomeres, or DNA structures located at the end of chromosomes. For example, a sparrow with a structurally bigger body has shorter telomeres and this biological predicament reduces the ability of the tissues and cells to function at its optimum.

"Growing a bigger body means that cells have to divide more. As a result, telomeres become eroded faster and cells and tissues function less well as a result," explained University of Glasgow's Zoology Professor Pat Monaghan.

Increased growth could lead to DNA damage, which could be why bigger or taller people have shorter telomeres compared to shorter individuals. A tall physique may have advantages, but it also increases mortality risks.

Telomeres are like plastic caps attached at the tip of shoelaces protecting the genetic material from damage when cells divide. Longer telomeres can be advantageous in the biological aging progression and in the wide-ranging disease protection and risk.

"The reduction in telomere size that followed the increase in body size suggests one important mechanism that limits body size evolution in wild animal populations," said Norwegian University of Science and Technology's population ecology associate professor Thor Harald Ringsby.

The study was published in the journal Proceedings of the Royal Society Biological Sciences on Dec. 2. and was funded by The Research Council of Norway and the European Research Council.

Photo: Guilherme Nicholas | Flickr