A plan for all seasons

Study lifts lid on how we're all affected by changes in light

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new study is an early, but important, step that reframes how we conceive human circadian rhythms.

HUMANS are still "seasonal" creatures despite advances of 24-hour technology, according to new research.

Our body clocks are still "wild at heart" tracking the seasonal changes in daylight, say American scientists.

They say their findings, published in the journal npj Digital Medicine, could enable new ways to probe and understand Seasonal Affective Disorder.

Study author Dr Ruby Kim, Assistant Professor of mathematics at the University of Michigan, said: "Humans really are seasonal, even though we might not want to admit that in our modern context.

"Day length, the amount of sunlight we get, it really influences our physiology.

"The study shows that our biologically hardwired seasonal timing affects how we adjust to changes in our daily schedules."

The research team say their findings could also open new areas of inquiry for other health issues connected to the alignment of our sleep schedules and circadian clocks.