Entering the realm of old age requires sacrifice. Many processes in our body change when we have lingered in adulthood for a while.
The extent of those changes is quite individual and depends on, among others, genetics, metabolism, lifestyle, and environment. Still, as we age our immune function declines, the risk for cancer increases, muscle turns flabby or disappears, joints creak, connective tissue loosens, and memory is no longer what it used to be. Even our microbiome and body shape change.
Our skin changes as well.
What was once smooth becomes wrinkled. Our skin also tends to become thinner as we age (we shed skin cells all the time, and most old bodies can’t keep up with making new ones). …
Once upon a time, not that long ago, a philosopher developed a famous thought experiment on consciousness by asking what it is like to be a bat.
The answer, according to Thomas Nagel, who wrote the paper, is not only ‘we don’t know’, but also ‘we can’t know’. (Lest we got lost in philosophical discussion here, read the linked Wikipedia article above, or the paper itself.)
We also don’t know what it’s like to be a bat’s prey.
Probably not fun, though.
One of the reasons for the ‘can’t know’ from a few sentences ago, is that bats have a sensory apparatus that is unlike ours in that most of them rely very much on echolocation (although there are cases of human echolocation). By producing sound and interpreting the echoes of the sound waves, bats can do impressive feats of aerial acrobatics. …
The vampires in many folk tales share a few characteristics, among them immortality and a taste for blood. Actually, these two might be link, as we’ll see below.
Another interesting commonality is that vampires seem to prefer young victims, sinking their canines into necks belonging to people in the prime of their life.
This is, of course, because it makes for a greater, more dramatic story.
But the imaginary bloodsucking night people might be on to something.
Growing up, many of us were fascinated by dinosaurs. Rightfully so, since those (often) giant reptiles held sway over earth for more than 200 million years. In comparison with the dinosaurs’ tenure, human existence has been but a blip on the radar of eternity (strained metaphor, I know).
We devoured (puns!) the Jurassic Park movies and any book with cool dinosaur illustrations.
Despite the terrible lizards’ long reign, the term ‘dinosaur’ was only coined in 1842 by famed paleontologist Richard Owen. But that doesn’t mean humans haven’t been unearthing dinosaur fossils for a long time before that.
The ancient Greeks and Romans reported bones of giants and monsters, later slightly modified to be constrained to biblical giants and creatures. In the far East, the people found dragon bones, often ground into powders to be used in traditional medicine. …
In 1946, George Orwell — of Animal Farm and 1984 fame — wrote an essay entitled ‘Why I Write’. The essay was part of a collection of famous writers’ personal motivations, published in the magazine Gangrel.
Orwell (whose real name was Eric Arthur Blair) died prematurely at age 46 due to tuberculosis. Orwell served as police officer in Burma, London, and Paris before becoming a teacher. Later, he was a bookshop assistant, went to serve in the Spanish Civil War, and worked in the BBC’s propaganda department during WWII.
Throughout all this, though, he wrote incessantly.
As he recounts in the essay, he knew he wanted to be a writer at age 5 or 6. He actually started by writing poems. As time progressed, he began writing short stories. He also shares how he kept up a continuous inner narrative about himself — a “diary existing only in the mind”. …
To beat death has been a goal for some people as far back as we have written accounts. One of the earliest known stories, the epic of Gilgamesh (written over 4,000 years ago) involves the quest of the hero for immortality.
Spoiler: he didn’t succeed.
Most of us want to grow up, but nobody wants to grow old.
Old age, after all, comes with a suite of unpleasant changes.
Maybe it was a science class where you first met mercury. The chemical element with the symbol Hg is fascinating. It’s a liquid, but it doesn’t act like another liquid.
This is because it is the only metallic element that is in the liquid phase under conditions of ‘standard’ pressure and temperature. Since mercury is a metal, the bonds between its atoms are quite strong. This results in a very high surface tension, which explains why mercury doesn't splash like water, but rather rolls and glides across surfaces — mercurial, you might say.
The fact that mercury doesn’t stick to glass but still responds well to temperature fluctuations by changes in volume. Hence, its most well-known application is its use in thermometers. …
No one escapes the ravages of age. And not a single part of our bodies is spared, not even our microbiome.
This suggests that there are many pathways that are involved in aging. Some substances that are being researched for their supposed anti-aging properties (such as rapamycin) may affect some of these pathways. The interventions we would really like affect so-called downstream targets, molecules that exert their influence on the initial steps of one or several pathways. Another name for these potential molecular elixirs of life is the ‘master regulators’.
But what about the supplements and/or exercise regimes that are touted by (social) media influencers? Take these omega 3 supplements and your brain will stay healthy for longer. Use this HIIT workout (even though real HIIT is much more intense than many of the workouts that are called HIIT these days) and you’ll be building muscle/burning fat all the way into your grave. …
The stars might seem eternal, but they too have a limited lifespan. Near the end of their lives, stars go through runaway nuclear fusion. They go ‘boom’. This explosion is known as a supernova.
Supernovae can be as bright in the night sky as an entire galaxy. Big boom.
Following the supernova a star collapses into a neutron star or black hole, or is entirely destroyed — the star’s eventual fate depends upon its mass.
We all begin life as a single fertilized cell. That cell, though, has to develop into a full-fledged human being with many different organs and tissues, each of which is composed out of different cell types.
How do we go from one cell to many different types of cells?
Stem cells are cells that can differentiate into many different cell types. As embryo, we have plenty of pluripotent stem cells that can develop into all of the body’s cell types.
As we age, though, the number of stem cells drops precipitously.
Pluripotent adult stem cells are quite rare, restricted to bone marrow and a few other tissues. Most adult stem cells are multipotent (restricted to a specific ‘lineage’ of cells, for example, different types of muscle cell) or unipotent (only able to become one specific cell type). …