When kept in 12 hours of light and 12 hours of darkness the mice - which are nocturnal - began consuming more food when the lights were on as early as the first week.

Kirkland will be kept in hospital for 24 hours of observation after sustaining a head injury in a challenge with Johan Elmander, but Wigan manager Roberto Martinez said the early signs were positive.

The denizens were all enjoying the usual afternoon nap of an hour or so which the exceedingly early hours kept in summer-time rendered a necessity.