Analysis of air conditioning units points to the origin of the human species, researchers say

The internal climate in US houses is 'essentially the same' as the outdoor climate in Kenya

Academics monitored homes around the US for more than a year (PA)

A study of the settings used on air conditioning units in the US has provided clues about the origin of the human species, according to a team of scientists at North Carolina State University.

The researchers found that the average interior climate created in North American homes, using central heating systems and air conditioning, is “essentially the same” as the outdoor climate in west central Kenya, a region that is rich in humanoid fossils and is considered by many to be the cradle of humanity.

A team of academics led by Michael Just, a doctor of philosophy and plant biology, asked volunteers to install devices in their homes that logged the temperature and air moisture every hour.

They monitored the homes, which were located across the US, for more than a year, measuring seasonal changes in temperature inside houses and comparing them to outdoor climates from around the world.

The study published by The Royal Society, the world’s oldest independent scientific institution, found that individuals subconsciously sought temperatures that mirrored the habitat of their ancient ancestors millions of years ago.

Professor of applied ecology Rob Dunn, one of the authors, said: “It’s a preliminary report – but what we see so far is in line with the idea that we are creating the conditions our ancestors would have existed in and would have felt natural for them.”

In the findings there were some slight variations between homes in different states.

The study suggests that the internal temperatures of homes in Alaska most closely matched the outdoor climate of Namibia, while Florida homes had an internal climate that was more like Ethiopia.

The academics behind the report say further studies that look at central heating systems around the world would be likely to throw up other cultural differences.

“In some cultures around the world communities may be unable or unwilling to control their internal environments to the same degree that North Americans do,” said Dunn. “Americans are willing to expend huge amounts of resources controlling internal climates to maximise their own comfort."

The team from North Carolina State University believe their findings could form part of future discussions around energy efficiency.

“The questions we are asking could seem quite quaint,” said Dunn. “But if people are going to continually recreate these specific climate conditions wherever they live in the world it will have significant repercussions for global energy usage.”

The team say that human beings can feel comfortable in a wide range of temperatures and there is an argument for people to try and reign in the subconscious desire to tightly control temperatures in their homes.

“Hopefully this research will start a new debate about how much energy we really need to use to power interior climate control devices like air conditioning,” said Dunn.

Space heating and air conditioning accounts for nearly half of all energy use in US homes, according to the US Energy Information Administration.