Most mutations involve typos: Something bumps a cell's elbow as it's copying DNA, and the wrong letter appears in a triplet - CAG becomes CCG. Sam Kean appearbumpcag Change image and share on social
All human beings are, in fact, born with dozens of mutations their parents lacked, and a few of those mutations could well be lethal if we didn't have two copies of every gene, so one can pick up the slack if the other malfunctions. Sam Kean bearbeingcopy share on social
Lithium makes a fine battery because it's a scarily reactive metal. Pure lithium ignites on contact if it touches water - a flake of it would sizzle and fry on the water-rich cells of your skin. Sam Kean batterycellcontact Change image and share on social
Although it's the hub of the nervous system and the ultimate terminus of every nerve, the brain itself lacks enervation and therefore cannot feel pain. Sam Kean brainenervationfeel Change image and share on social
Microchimeric sharing means that, even if the mother loses a child, she'll have a small memento of him or her secreted away inside her. Similarly, a bit of our mothers live on in all of us no matter how long ago Mom died. Sam Kean agobitechild share on social
Whereas recessive traits require two bad copies of a gene to become noticeable, a dominant trait expresses itself no matter what the other copy does. A benign example of dominance: If you inherit one gene for sticky wet earwax and one gene for dry earwax, the sticky earwax gene wins out every time. Sam Kean badbenigncopy share on social
The amygdala is one of those brain structures that a lot of people know a little bit about, and there's a definite tendency to conflate the amygdala and the fear response itself - as if the amygdala, and the amygdala alone, 'causes' fear. Sam Kean amygdalabitebrain share on social
The price of diamonds can vary greatly depending on size, cut, color, and other factors, including whether they have a history. But because of the rarity of blue boron diamonds, they often fetch more money than gems of similar quality. Sam Kean blueboroncolor share on social
Atoms of Element 118 fill an outer shell with electrons, creating a special type of element called a noble gas. Noble gases are natural turning points on the table, ending one row and pointing to the next. Sam Kean atomcallcreate share on social
X-rays revealed that some people were born without a corpus callosum, and they seemed just fine. Sam Kean bearcallosumcorpus Change image and share on social