Genetic Pre-Dispositions: Nature's Misunderstood Gift

What is Evolution?

Everyone has heard of evolution or spoken about it figuratively within a conversation. But what really does it mean?

It’s a broad term that refers to the genetic change overtime in an organism according to the pressures exacted by its environment. Still confused? Not surprisingly this is a complex and multifaceted theory that can’t be explained within a sentence.

2.5 Million Years Ago - The Habitat of An Ape

An ape is a herbivore that spends most of its time living in trees of an equatorial rainforest jungle.

The Ape is perfectly adapted to its environment:

• The Ape can climb well to reach its food which mostly is found in the form of fruits in the trees.
• The Ape has adapted to spending most of its life in trees including sleeping,
• The Ape has simple social structures that allow mothers to bring up children whilst the men look out for or attempt to defend themselves from predators.

Apes have some limited learned ability like the folding of branches into simple structures to be used as beds or use a twig to extract ants from within a tree to provide some extra protein.

They rarely spend time on the ground and as such their abilities on the ground are limited, they have shorter legs and are more comfortable on all fours there. For this reason, they rarely visit the forest floor save for some rare scavenging opportunities, there has to be a big calorie pay off though as on the forest floor they are more vulnerable to predators.

Ice Age Forming: Environmental Pressure to Survive

Unfortunately for the apes, the environment is changing. Forces out of their control which include: the orbital distance of their planet from the sun, oceanic currents, and the polar axis of their planet or any other innumerate variables that could be involved are causing the climate to cool.

In fact, the Apes climate is cooling so much that year after year the polar ice caps are growing and accruing more ice. This doesn’t happen immediately but slowly over thousands if not millions of years the ice is spreading.

Whats more of the planets water gets locked up in ice there is less in the atmosphere creating a dryer climate. Rainforests start to reduce over time; patches of grasslands start to appear between clumps of forest as there isn’t sufficient precipitation to support as many large trees.

A Small Evolutionary Jump: 10,000 Years Later

10,000 years have gone by since the environment started changing. Some Apes died due to natural selection, but other survive – but what’s changed with the new Apes? Outwardly, they look broadly similar, but their environment seems quite different. You notice:

• That they aren’t as clumsy walking on the ground and possibly, just maybe you notice their legs appear slightly longer.
• They also tend to spend less time on all fours; this makes them more adept at crossing grass land and getting a better vantage point to see predators coming from afar.
• You notice that when in the open some of them grab sticks as a tool or weapon in case they were attacked by a predator, this is facilitated by the fact they spend less time on all fours allowing them to use their hands.

The Strong Survive: Natural Selection

What allowed this ape to make small and subtle changes over the ten thousand to better suit its environment? The process is known as natural selection and it is an ever present subtle but constant pressure that affects all organisms fighting to survive in their environment.

As the climate changed over time the pressures on these apes changed. Members of the troop who were better at travelling over open ground or standing up right to see predators were less likely to be eaten, their genetics were more likely to be passed on. 

Genetic mutations giving slightly longer legs facilitated the ability to stand upright making genes more likely to be passed on (because the Apes did not die, and therefore we able to pass their genes).

Due to the environment changing, different types of foods were available on the grasslands such as fresh animal kills, the apes most able to take advantage in this new source of calories were more likely to survive and more likely to pass their genes on.

Over thousands of years, the Apes that had more suitable genes for their environment were able to survive, procreate, and pass on their genes. The ones who did not have favourable genes, died. This ends their gene bloodline - ensuring poor genes are not passed on.

A Big Evolutionary Jump: 1 Milliion Years Later

Let’s skip forward another million years now but still following the ancestors of the original troop of apes we considered.

The continual cooling of the earth has caused it to enter an ice age making the climate very dry. The equatorial rain forests have mostly disappeared to be replaced by grasslands.

Our apes are now mostly upright and look quite different;

• Their hands are free allowing them to interact with their environments in ways not possible for quadrupeds.
• They frequently carry sticks with which to defend themselves against far bigger predators.
• They don’t spend any time in trees, but their shoulders that used to be articulated for swinging have now been adapted so they can use them to throw.

This has opened up a world of possibilities in both defending from predators and access to prey. It also has facilitated more complex social structures as the ability to work together to achieve goals proves far more fruitful for the troop as a whole than individual endeavours.

In case you haven’t guessed by now this story is analogous to human evolution.

Hopefully it illustrates the point that evolutionary pressures are subtle and constant overtime. These pressures shape an animal into a new species - This is evolution.

What has this go to do with Health?

You’ll note that there isn’t an instance where it would be advantageous to get diabetes, or heart disease, autoimmune disease or cancer.

In fact these conditions would have inhibited an organism to survive to the extent that it’s very unlikely that these genetics would continue to get passed on.

Evolution doesn’t make mistakes, it makes genetics that are designed to thrive in its correct environmental. Simply put, animals who develop disease will die, and their genes won't continue.

I can hear you thinking at this point; “but we know that there are genetic pre-dispositions to loads of these diseases”. Yes that’s correct, there are genetic predispositions to chronic diseases, but again, evolution doesn’t make mistakes – so how do these genes exist? 

Genetic Pre-Dispositions: Nature's Misunderstood Gift

Between 250,000-10,000 years ago your ancestor’s ability to get fat determined your ancestors ability to survive freezing cold ice age winters in northern Europe.

Insulin resistance in an environment of scarcity spares energy in your body for brain and reproductive capacity. The desire to over consume or crave hyper caloric hyper palatable food comes from a drive to find food, this is an evolved drive that made you a great person to know when it came to finding food.

Hormonal irregularities that contribute to breast cancer make you more fertile and give you an ability to bare more children in the right environment. The genes associated with autoimmunity protect against parasites and water bourn hepatitis.

So with a few very recently evolved (post-agricultural revolution) genetic conditions (including sickle cell anaemia, haemocrhomatosis, and cystic fibrosis), most predisposition to disease comes from genetics that were advantageous in the environment they evolved in but are not a good biological fit in the modern environment.

How To Choose The Genetic Destiny For Your Health

If we accept that our genetics were designed to thrive in a specific environment, we can start to decipher what that environment may have been and in cooperate practices to mimic that environment so as to give our biology the best possible chance for good health outcomes. 

The scientific literature is already awash with evidence that this is the case. For instance, people who eat whole foods tend to have better health outcomes – could it be that is because these are more like the types of foods we evolved alongside?

People who exercise have better health outcomes – as our ancestors were extremely active on a daily basis. Our immune systems work better when we are healthy because our immune systems were designed in the context of our metabolically healthy ancestors.

All of these practices that promote health mimic your evolved environment even though you live in a modern one.

What this means is you can literally have your cake and eat it too. You can have all the benefits of modern life whilst also instilling practices that signal to your biology in the same way the environment your ancestors evolved in did. 

Discover Your Evolutionary Health

Now there is nuance here. For example – what exercise and how much should you do or which whole foods and in what proportion. Whilst some people are able to work this out for themselves, to many others, it is not so intuitive.

Some people can feel they’ve done the right thing their whole lives only to end up with sub-par or undesirable health outcomes.

This is where Biospan can come in. We take your health history, likes, dislikes, goal, and everything else to match you with a nutrition intervention that would be most evolutionary consistent with your biology for the expression of health.