Why keto diet does not restrict tumour growth & an ancient predator is now a timid herbivore

ScientiFix, our weekly feature, offers you a summary of the top global science stories of the week, with links to their sources.

Representative image | Keto diet | Pixabay

Bengaluru: The ketogenic diet was developed as a way to curb the growth of tumours, which feed on sugar. Previous research has suggested that low calorie and ketogenic diets help prevent conducive conditions for tumour growth or spread by lowering blood glucose and insulin levels.

Researchers at Koch Institute for Integrative Cancer Research at MIT compared tumour growth in two groups of mice, one with a calorie restriction diet and another with the ketogenic diet. They discovered that mice that were fed a calorie restricted diet showed slowed pancreatic tumour growth, but mice with the keto diet did not.

The scientists concluded that it is not only sugar restriction, but also the balance of the kind of fats being consumed that can affect growth of tumours. While low calorie diets deprive the body of sugars, high fat makes up for metabolic processes depraved by sugar, said the team. The findings were published in the journal Nature this week. More on Inverse.

African grey parrots have will power, self-control, patience

It has been seen that some highly cognitive animals like dogs and dolphins have the ability to use their will power and self-control to delay gratification for a better reward. Scientists at the Max-Planck-Institute for Ornithology tested four different species of parrots for their ability to display patience by resisting food.

They were first given a food they did not prefer — sunflower seeds, and then were made to wait for food they liked — walnuts. If the parrots waited, the researchers presented them with walnuts. Both foods were visible to the birds through a transparent screen.

The researchers found that African grey parrots were able to wait nearly 30 seconds for the walnuts, while great green macaws waited just 20 seconds, blue headed macaws waited about 12 seconds, and blue throated macaws a mere eight seconds. An African grey called Sensei was able to wait for up to 50 seconds.

The research was published in the journal Animal Cognition. More on Earth.com

Giant worm predators lurked in ancient sea floor

Fossil evidence has revealed that giant worms used to lurk underneath the seafloor in Taiwan, hiding to capture fish, about 20 million years ago. These worms left trace fossils of burrows that were over six feet long and one inch wide.

Modern versions of these worms are called sand strikers and are just few inches to a few feet in length. However, these fossils reveal that the prehistoric versions these worms were much larger, quicker, stealthier, and dangerous. The imprint of the fossilised tunnel indicate “violent” events where a worm darts out of the burrow with a lot of strength rather than slowly crawl out.

The fossils were discovered first and attributed to a new prehistoric species only in 2017. The findings were published in the journal Scientific Reports. More on National Geographic.

Terrifying Australian dinosaur was actually a shy herbivore

A new analysis of fossilised footprints from Australia, which were first discovered 50 years ago, have revealed that the creature they belonged to were actually timid herbivores instead of terrifying predators. When they were discovered, the tracks were thought to have been made by a bipedal predator about 200 million years ago. They were even thought to be the earliest evidence of a carnivorous dinosaur.

Now scientists have analysed a cast of the prints using advanced 3D imaging techniques, and discovered that many impressions thought to be claw marks were actually just drag marks from their claws. A previously thought part of the bone was actually a part of a nearby rock.

The researchers discovered that the dinosaur in fact had a short stature and narrow foot, and was herbivorous. The findings were published in the journal Historical Biology. More in the New York Times.