Animals have astonishing abilities, which help them survive when the circumstances are difficult. Many of them, including bears, hibernate. The state is characterised by low body-temperature, slow breathing and heart-rate, and low metabolic rate. Hibernation most commonly occurs during winter months. In case of birds, they add grow more feathers to help them stay warm and help in their migratory flight. But there is one sub-species, the palm-sized black-capped chickadee, which add brain tissue instead of feathers when they are hibernating.
This extra brain power helps the bird remember the site where it buried the food item for sustenance. When it gets hungry in the winter, the bird returns to these burial sites.
Some chickadees are able to grow the brain by nearly one-third by adding new nerve cells, enabling them to recall hundreds of spots where the food is buried.
According to National Library of Medicine (NLM) of the US government, these birds are able to achieve this incredible feat because the memory portion of their brains - the hippocampus - is designed to increase in size.
"The total size of the chickadee hippocampus increases in autumn and winter as does the rate of hippocampal neurogenesis. The hippocampus is necessary for accurate cache retrieval in food-storing birds and is much larger in food-storing birds than in non-storing passerines," the NLM said on its website.
This ability could cause human to envy the bird as they experience "senior moments" as they age, which causes them to forget things they held in their hands or kept somewhere.
"To see this happen under natural conditions is truly awe-inspiring. Our hypothesis is that this exaggerated growth occurs when the birds need it the most," Colin Saldanha, assistant professor of biological sciences at Lehigh University, told Science Daily.
This supercharged memory thus allows this tiny species of bird to survive in harsh winters. The bird is found in large areas of northern US and southern Canada and is identifiable by its black-coloured head, and small body.