Viruses can cause disease. As can bacteria and various parasites.
But invasion by those minuscule marauders is not the only cause of disease. Normal internal processes can go wrong as well. For example, mutations can have either a direct or indirect effect and lead to internal errors.
(Genetics, of course, also affects how our bodies deal with external pathogens such as viruses and bacteria.)
Thanks to increasingly better methods to read and analyze DNA, many disease-causing genes have been identified. …
As soon as machine learning systems get better at designing other machine learning systems than human experts, the age of Homo sapiens will come to an end. After all, those slightly better systems will build systems that are slightly better still. Boom, exponential improvement.
…a hypothetical agent that possesses intelligence far surpassing…
You are your microbes. That is an exaggeration, but ever since we have the research tools to spy on the microbes in and on our bodies, we see their tiny fingerprints everywhere.
Especially the microbial guests in our gut are seemingly involved in many aspects of our lives, from how we metabolize food and how hungry we get to our risk for certain diseases, such as Alzheimer’s, and even our personality traits. They influence our risk for cancer, and they could improve chemotherapy.
Of course, it’s not always clear whether the observation is cause or effect. Hidden factors (‘confounders’) could…
Prosthetics — artificial replacements for lost body parts — have a long and venerable history.
The earliest evidence of prosthetics we know of is about 5,000 years old.
Our bodies are complex systems. This has its perks, but unfortunately, it also means that a lot can go wrong. When some part(s) of that system is/are no longer able to perform their proper job, we call it a disease or injury.
External factors, such as pollution, poison, parasites, infections, and so on can cause disease. However, intrinsic factors can cause errors in our bodies as well.
Aging is inevitable.
At least for humans.
At least for now.
Even though some organisms buck the trend (see the fish that refuses to age, for example), most complex multicellular animals age.
There are many ideas about why this happens, but they can be roughly grouped into two categories: damage-related and programmed factors.
Damage-related hypotheses focus on the accrual of damage over the lifespan: DNA damage, oxidative stress, and so on. Eventually, our physiology fails to keep up with the maintenance and repair, and the cascade of aging begins.
Programmed factor hypotheses revolve around more intrinsic factors, perhaps even a…
Hundreds of billions of brain cells with trillions of connections is a puzzle with a lot of pieces. For that complex puzzle to function properly, it needs to ensure that its pieces fit together as intended. (And we’re still discovering new pieces.)
In 1901, German psychiatrist Alois Alzheimer met a patient — a fifty-one-year-old woman — who suffered from progressive memory decline, grew increasingly disoriented, and was occasionally taken by paranoid delusions, including a cheating husband or someone out to kill her.
Alois Alzheimer followed up her case until she died in 1906. His case report, published in 1907 (you can read an English translation of the original here), was the first official description of Alzheimer’s disease (AD). Of course, dementia in its many guises has been known for a long time before that, dating back at least to the ancient Greeks.
Few mammals are as majestic and mysterious as whales. Size, song, and sophisticated brains all come together in these ocean giants.
Of course, not all whales are massive. Dolphins, for example, are the smaller, lither cousins of the gigantic blue whale.
Whales, like us, are mammals. The difference is that their ancestors turned their backs to land and ventured into the water again. It’s hard to pinpoint exactly when this happened and the transition to an aquatic life will have taken some time. …
The microbial communities, or microbiomes, that inhabit our bodies tend to become close partners over our lifetime.
We have many of those microbiomes (which include viruses). Each of us walks around with a skin microbiome, nasal microbiome, and so on. But the star of microbiomes is without a doubt the gut microbiome
The microbial partners in our intestines might affect how we metabolize food and how hungry we get, but also our risk for certain diseases, such as Alzheimer’s, or our risk for cancer, and even our personality traits. Of course, cause and effect aren’t always clear. …