Will we reach maximum possible variants of our species?

[Guttairc]

I was thinking, they say dinosaurs was wiped out by meteorite, but all animals under 50 kg survived. Hence we have chickens, crocodiles etc. today. But if life can be wiped out by a meteorite, it means that our planet isn`t safe after all, which I doubt a little. I think what reappy happened instead, was that maximum of possible variants of dinosaurs were born, so they naturally became extinct for another species to take over. Since humans are more intelligent than dinosaurs were, it`ll take longer perhaps to reach maximum. It can`t be like an infinite variants, it has to stop someday, or will it go on forever? They say 117 billion people have been born so far, all different

 

[Infirmus]

They say 117 billion people have been born so far, all different

ChatGPT says...

"DNA sequences are composed of four nucleotides (adenine [A], cytosine [C], guanine [G], and thymine [T]). The number of possible combinations of DNA depends on the length of the sequence. The human genome consists of approximately 3 billion base pairs, so the total number of possible combinations is:

This is an astronomically large number, vastly exceeding the number of atoms in the observable universe."

Now, the number of variations...

I suppose that "incomprehensibly vast" and "astronomically large" means that we're still long way before reaching the "maximum possible variants".

 

[Infirmus]

I didn`t know there were that many possibilites

Me neither. 10 to the power of 900,000 possible "human variants" compared to 10 to the power of 80 atoms in the observable universe! Mind boggles.

 

[Infirmus]

Well, if we see soul as something immaterial and separate from the body, then indeed the four nucleotides have nothing to do with it (or don't affect it directly). I am afraid, however, that even AI cannot calculate the possible number of different souls.

Interesting idea for a thread!

 

[chevyontheriver]

Me neither. 10 to the power of 900,000 possible "human variants" compared to 10 to the power of 80 atoms in the observable universe! Mind boggles.

The biological constraints on this are also astronomical. Think of a gene encoding a very necessary enzyme. Most of the single mutations of that gene sequence will be fatal. Some won't really matter. A few will make any noticeable difference. Point being even though there are an insane number of ways to lign up the C, A, T, and Gs of DNA almost all of them are going to fail to make a living thing. We probably only have a few trillion ways to make a healthy human being.

 

[Infirmus]

We probably only have a few trillion ways to make a healthy human being.

Only!

AI says "trillions to quadrilions or more". Still quite impossible to even imagine...

How many ways are there to make a healthy human being (DNA viable variations)?

The number of possible viable DNA variations for a healthy human being is staggeringly large due to the complexity of genetic inheritance and the vast combinatorial possibilities involved. Here's an overview:

1. Chromosomal combinations from parents:​

• Humans have 23 pairs of chromosomes, one set inherited from each parent. During the formation of gametes (sperm and egg), chromosomes undergo recombination and independent assortment.
• Each parent can produce 2232^{23}223 (about 8.4 million) unique combinations of their chromosomes.
• Combining gametes from both parents results in 223×223=70×10122^{23} \times 2^{23} = 70 \times 10^{12}223×223=70×1012 potential combinations of parental chromosomes.

2. Genetic recombination:​

• During meiosis, homologous chromosomes exchange genetic material, creating further genetic diversity. The number of possible outcomes from recombination adds another layer of complexity but isn't easily quantifiable in a precise number.

3. Mutations and single nucleotide polymorphisms (SNPs):​

• The human genome has about 3 billion base pairs, and there are millions of locations where variations (mutations or SNPs) can occur.
• Most of these variations are neutral or have no significant impact on health, while a subset can contribute to health, disease resistance, or susceptibility.
• Considering viable mutations, the number of healthy combinations is vast but constrained by the need for functional proteins and non-harmful genetic changes.

4. Epigenetic factors:​

• Environmental and epigenetic factors influence gene expression and contribute to phenotypic diversity. These factors aren't directly genetic but add layers of variability in health and traits.

5. Constraints on "healthy":​

• Many genetic variations lead to non-viable or disease states, reducing the pool of "healthy" possibilities. However, the human genome is robust, with redundancy and mechanisms to compensate for many deleterious mutations.

Rough Estimate of Viable Variations:​

While it's impossible to calculate precisely, estimates of viable genetic combinations for healthy humans range in the trillions to quadrillions or more when considering recombination, mutations, and SNPs. The number is effectively infinite in practical terms, given the limits of computation and the complexity of genetic interactions.