Why Do Dogs Tilt Their Heads? Scientists Look at What’s Going On in Their Minds:

You’ve probably seen dogs tilt their head. It’s adorable, but why do they do it? According to scientists, it may be a sign of concentration and memory recall. Several animals, including humans, present an asymmetry in the way they move or perceive the environment through their senses. In dogs, these asymmetries manifest in behaviors such as tail wagging, nostril use while sniffing, or even paw preference when trying to grasp something out of their reach. A test was conducted to find how head tilts help dogs perceive their environments by having owners request toys by name and observing head tilts among forty different dogs. Through analysis of the head tilts during the experiment, head tilts were consistently similar across dogs and those who did head tilts more often seemed to associate the name with the toy faster than those who didn’t. Thus, head tilts in dogs seem to be a means for dogs to understand their owners and though we don’t know everything about them yet, is a step in the right direction to understand our furry companions.
A mineral found in a diamond’s flaws contains the source of some of Earth’s heat:

The tiny gray blobs of mineral embedded in this slice of clear diamond are the first samples of newly named davemaoite, a calcium silicate perovskite mineral that only forms in the lower mantle.
A tiny bit of rock trapped inside a diamond is now opening a brand-new window into what the planet’s lower mantle looks like. Inside the diamond is a newly identified silicate mineral dubbed davemaoite that can only have formed in Earth’s lower mantle, researchers report. The diamond was found in a Botswana mine at around the upper bounds of the Earth’s lower mantle and, due to the new mineral being preserved in the diamond, it maintained its chemical structure. Because of this, the mineral was found to confirm certain radioactive materials create heat deep in the earth, confirm the water cycle due to ice formations on the material, and the carbon cycle through the formation of its diamond container. Also, davemaoite was found to have unusually high levels of potassium compared to what was projected, which further supports the idea that the mantle’s composition is much more complex than we ever thought.
For stem cells, bigger doesn't mean better:

MIT biologists have answered an important biological question: Why do cells control their size? A new study examining blood stems cells suggests that the larger a cell is the higher the decline in function of stem cells. The researchers found that blood stem cells, which are among the smallest cells in the body, lose their ability to perform their normal function replenishing the body's blood cells as they grow larger. However, when the cells were restored to their usual size, they behaved normally again. The researchers also found that blood stem cells tend to enlarge as they age. Due to this discovery, many other studies examining cell growth in the intestinal tract and examinations studying DNA damaged cells have qualified the idea that smaller is more efficient. New drugs like Rapamycin, a drug that can inhibit cell growth, are now being used to treat cancers and prevent organ transplants due to their ability to extend the lifespans of other organisms. This new relationship between cell size and stem cell efficiency has opened up new doors to the treatment of disease and presents new opportunities for the human lifespan to become longer than it ever has been.
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A new mineral from deep within Earth was found in a diamond’s flaws | Science News