Last Week in Science (24th Dec 2023)

Those dark brown eyes

What secrets do those dark brown eyes hold.
Are we the ones who had the dogs mold?

Dogs melt our hearts with their puppy eyes. Have you wondered if there is a reason why most dogs have brown eyes? Scientists at Teikyo University of Science might have found the answer. The scientists showed photos of dogs with brown and light colored eyes to individuals and asked them to rate the dogs based on whether looked aggressiveness, friendliness and intelligence. They found that the dogs with dark eyes were seen as friendlier and non aggressive and also less intelligent - exactly how a puppy would be like.

Light colored eyes, as present in wolves are advantageous for communication in the wild because of the ease of picking up cues from a dark colored pupil on a light background of the iris. And we all know how scary a wolf is. So, the dark eyed dogs might have been selected by humans during the domestication of dogs. One reason could be that the pupils look larger in dark colored eyes and humans prefered those dogs as larger pupil appears to be a sign of friendliness and also babies have a larger pupil.

But more studies need to be done as how can we forget the drama queen - siberian huskies who have blue colored eyes and are still loved around the world? But no wonder they do look scary as a wolf!


Talk, talk and talk

Could not stop yourself from talking to your toddler? Guess what, it helps the toddler as well. Recent research at Harvard University shows that the more the parents talk to their kids, the more the kids talk and have larger vocabularies. 

The scientists made the kids wear a small recording device, not to spy on them, but to record how much are they speaking or blabbering and how much of the talking is happening in their environment. They made these recordings in 12 different countries from 1001 kids to get 40,000 hours of recording from 2865 days. They also found that there were no differences in how much a kid talked because of the socio-economic status of the parents - mother being less educated or the family being poor.

The sleepy reindeers

Eat, sleep and repeat - is not the only mantra.
Sleep while you eat - says the Santa.

What do you like the most after a fulfilling meal? Sleep, right? What if you could eat and sleep at the same time? That will definitely save some time for those slow eaters. Researchers at University of Zurich, Switzerland have found that reindeers show sleep like brain activity while they ruminate - an activity that is similar to what cows do i.e, chewing the food stored in stomach long after they have eaten it.

What makes this study interesting is the following! When the reindeers were kept awake for 2 hours longer than their regular active time by making loud sounds or giving them tasty treats, then their need to sleep during their active team increased. But if the reindeer had ruminated and were disturbed thereafter, then the need for sleep during active time was not seen. 

The reindeers eat as much as possible during the summers so as to bulk up for the coming winters when the food would be scarce. So, spending the maximum time eating by reducing their need to sleep separately lets them optimize their time. The reindeers thus save up time on sleeping because they can multitask.