Register | Sign In


Understanding through Discussion


EvC Forum active members: 57 (9189 total)
2 online now:
Newest Member: Michaeladams
Post Volume: Total: 918,912 Year: 6,169/9,624 Month: 17/240 Week: 32/34 Day: 4/6 Hour: 0/1


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
Author Topic:   Mutations Confirm Common Descent
sensei
Member (Idle past 137 days)
Posts: 482
Joined: 01-24-2023


Message 70 of 106 (907068)
02-18-2023 4:38 PM
Reply to: Message 1 by Taq
11-04-2022 1:25 PM


Thank you for providing evidence for common ancestry of primates.
I have two questions for you. How much of our human DNA are shared among all people today? And how much of it is shared with other primates?
I know I can look it up, but I'm asking you, so we can be sure that there is no disagreement on the numbers and you cannot accuse me of making anything up.

This message is a reply to:
 Message 1 by Taq, posted 11-04-2022 1:25 PM Taq has replied

Replies to this message:
 Message 71 by AZPaul3, posted 02-18-2023 5:00 PM sensei has replied
 Message 81 by Taq, posted 02-21-2023 11:21 AM sensei has not replied

  
sensei
Member (Idle past 137 days)
Posts: 482
Joined: 01-24-2023


Message 72 of 106 (907112)
02-19-2023 4:09 AM
Reply to: Message 71 by AZPaul3
02-18-2023 5:00 PM


I found this Nonhuman Primate Genetic Variant Database. I was hoping to extract more exact percentages of shared DNA between nonhuman primates from raw data.
Nonhuman Primate Genetic Variant Database
But the access link gives error page for me.

This message is a reply to:
 Message 71 by AZPaul3, posted 02-18-2023 5:00 PM AZPaul3 has replied

Replies to this message:
 Message 73 by AZPaul3, posted 02-19-2023 5:39 AM sensei has replied

  
sensei
Member (Idle past 137 days)
Posts: 482
Joined: 01-24-2023


Message 74 of 106 (907114)
02-19-2023 5:57 AM
Reply to: Message 73 by AZPaul3
02-19-2023 5:39 AM


I'm hoping to get a more accurate number and run different comparison methods. Also to understand the motivation behind different methods.
Then, put the numbers in a mutation model, probably some kind of Monte Carlo system, and see what data can be expected and what not.

This message is a reply to:
 Message 73 by AZPaul3, posted 02-19-2023 5:39 AM AZPaul3 has not replied

Replies to this message:
 Message 75 by Theodoric, posted 02-19-2023 10:55 AM sensei has replied
 Message 82 by Taq, posted 02-21-2023 11:22 AM sensei has replied

  
sensei
Member (Idle past 137 days)
Posts: 482
Joined: 01-24-2023


Message 76 of 106 (907150)
02-19-2023 11:11 AM
Reply to: Message 75 by Theodoric
02-19-2023 10:55 AM


Re: Hubris much
Why are you even talking when nothing but shit is coming out of your mouth?

This message is a reply to:
 Message 75 by Theodoric, posted 02-19-2023 10:55 AM Theodoric has replied

Replies to this message:
 Message 78 by Theodoric, posted 02-19-2023 1:00 PM sensei has replied

  
sensei
Member (Idle past 137 days)
Posts: 482
Joined: 01-24-2023


Message 79 of 106 (907192)
02-20-2023 6:49 AM
Reply to: Message 78 by Theodoric
02-19-2023 1:00 PM


Re: Hubris much
All you do here is troll

This message is a reply to:
 Message 78 by Theodoric, posted 02-19-2023 1:00 PM Theodoric has replied

Replies to this message:
 Message 80 by Theodoric, posted 02-20-2023 8:11 AM sensei has replied

  
sensei
Member (Idle past 137 days)
Posts: 482
Joined: 01-24-2023


(1)
Message 83 of 106 (907284)
02-21-2023 1:05 PM
Reply to: Message 80 by Theodoric
02-20-2023 8:11 AM


Re: Hubris much
Keep trolling. I do my research, I do not need your permission.

This message is a reply to:
 Message 80 by Theodoric, posted 02-20-2023 8:11 AM Theodoric has not replied

  
sensei
Member (Idle past 137 days)
Posts: 482
Joined: 01-24-2023


(1)
Message 84 of 106 (907295)
02-21-2023 1:38 PM
Reply to: Message 82 by Taq
02-21-2023 11:22 AM


It seems like a good argument for common ancestry of primates, ngl. Though I haven't looked at all of your sources yet, you made a convincing argument.
You got my attention, and if I can find data to verify independently as much as I can, we can discuss this further, if you wish.
Right now, what I was thinking, is if we look at humans only, for example, there is a percentage that is shared among all humans.
If we are in an ongoing evolution process, there is a portion of DNA in humans that is currently not shared among all individuals.
Depending on the part of DNA we are looking at, it can be anywhere between 0 and 1 fraction of total human population. For example DNA sequence for blue eyes may be around 8%, or perhaps more, as it may be present but not dominant.
Some of these varying DNA could reach 100% at some point and would promote to being fixed, shared in whole population.
From the data, we should be able to extract the rate of mutations and the fraction that fluctuate through the space between 0 and 1. We would need to make some assumptions on how much one sequence may have some beneficial advantages or not over other sequences. Then, hopefully, the model will give some predictions with margins of error, on how much different primate species should have in common. But I need to work out the model first and put in our data.

This message is a reply to:
 Message 82 by Taq, posted 02-21-2023 11:22 AM Taq has replied

Replies to this message:
 Message 85 by Taq, posted 02-21-2023 1:54 PM sensei has replied

  
sensei
Member (Idle past 137 days)
Posts: 482
Joined: 01-24-2023


Message 86 of 106 (907350)
02-21-2023 6:29 PM
Reply to: Message 85 by Taq
02-21-2023 1:54 PM


Well, I found sources from around 2018-2021, stating that 99.9% was shared among all humans. But you are suggesting it's lower, that in fact, for the vast majority of all DNA parts, if we'd pick one, there is likely to be one or a few individuals having a mutated sequence for that part?
Besides changes in mutation rates, population sizes are also changing. I hope I can find some rough estimates of population sizes throughout most of primate history.

This message is a reply to:
 Message 85 by Taq, posted 02-21-2023 1:54 PM Taq has replied

Replies to this message:
 Message 87 by Taq, posted 02-21-2023 6:33 PM sensei has replied
 Message 90 by Phat, posted 02-22-2023 10:47 AM sensei has replied

  
sensei
Member (Idle past 137 days)
Posts: 482
Joined: 01-24-2023


(1)
Message 88 of 106 (907369)
02-22-2023 3:31 AM
Reply to: Message 87 by Taq
02-21-2023 6:33 PM


So the 99.9% is if we would pick two random and unrelated individuals, they would share about 99.9% of their genetic markup.
Population size does matter for fixation rate, I suppose.
Maybe it's easiest to start a model for fixed population size n and mutation rate mu. And even start with a population where all DNA is identical. Then one question would be, after m generations, how many mutated bases (or genes) would have spread through 0.1 and 0.2 fraction of the population? And then same for 0.2 and 0.3, or more generally, between p and q.
Should we only consider point mutations for simplification? As I don't think it would affect the results much. But there are several types of mutations, and model may get too complicated.

This message is a reply to:
 Message 87 by Taq, posted 02-21-2023 6:33 PM Taq has replied

Replies to this message:
 Message 89 by Taq, posted 02-22-2023 10:40 AM sensei has replied

  
sensei
Member (Idle past 137 days)
Posts: 482
Joined: 01-24-2023


Message 91 of 106 (907420)
02-23-2023 2:16 PM
Reply to: Message 89 by Taq
02-22-2023 10:40 AM


It would be easiest to consider a model with a single DNA base, I suppose. In a population of size N, with zero mutations for this base, it may to to 1 mutation at rate mu * N per generation.
When n individuals have this mutation, it will go to n + 1 with probability p, and to n - 1 with probability 1 - p. For beneficial mutations, p would be greater than 1/2.
Numerically, this is east to iterate to find the distribution after a certain number of generations, for fixed p = 1/2 for example. Or draw a random p from a probability distribution, where we use estimates of beneficial mutation, neutral mutation, bad mutation ratios. But it gets complicated fast, as we would need some continuous probability distribution for p values between 0 and 1.

This message is a reply to:
 Message 89 by Taq, posted 02-22-2023 10:40 AM Taq has replied

Replies to this message:
 Message 92 by Taq, posted 02-23-2023 3:11 PM sensei has replied

  
sensei
Member (Idle past 137 days)
Posts: 482
Joined: 01-24-2023


Message 93 of 106 (907433)
02-24-2023 3:43 AM
Reply to: Message 90 by Phat
02-22-2023 10:47 AM


Re: Sensei seems sensible
Well, feel free to join the conversation, I suppose.

This message is a reply to:
 Message 90 by Phat, posted 02-22-2023 10:47 AM Phat has replied

Replies to this message:
 Message 95 by Phat, posted 02-24-2023 8:27 AM sensei has not replied

  
sensei
Member (Idle past 137 days)
Posts: 482
Joined: 01-24-2023


Message 94 of 106 (907435)
02-24-2023 3:51 AM
Reply to: Message 92 by Taq
02-23-2023 3:11 PM


That is the correct math for one dimensional random walk between two fixed boundaries. If the data would show different rates outside of the models confidence ranges, we may need to see if near extinction events could explain higher fixation for example, as fixation becomes more likely in smaller populations, with boundaries closer together.

This message is a reply to:
 Message 92 by Taq, posted 02-23-2023 3:11 PM Taq has replied

Replies to this message:
 Message 96 by Taq, posted 02-24-2023 10:46 AM sensei has replied

  
sensei
Member (Idle past 137 days)
Posts: 482
Joined: 01-24-2023


Message 97 of 106 (908127)
03-08-2023 5:18 AM
Reply to: Message 96 by Taq
02-24-2023 10:46 AM


Equlibrium for different popularion sizes.
I made these graphs. The model is for a single "neutral" DNA base, that can be A or B, so two possibilities instead of the usual four.
The first graph shows equilibrium distribution for the DNA for different population sizes N, for a "mutation rate" of mu = 10^-7.
It appears that when N * mu = 1, the distribution is a flat line.
For larger populations, the distribution seems to approximate the normal distribution, as the central limit theory predicts.
For the graphs below, each individual in the initial population has base A. Population size is fixed, each step consists of picking one random individual and copying it, with mu probability of a mutation happening for the copy. At the same time, another random individual dies to keep the population size fixed.
N steps counts as 1 generation.
The gray lines are for the distribution after 1, 2, 4, 8, 16, etc generations until equilibrium has been reached.
1
2
3
4
I tried to plot the average similarity between two random individuals against time. But this requires a lot of computer memory for large populations and too long computation time on my computer.

This message is a reply to:
 Message 96 by Taq, posted 02-24-2023 10:46 AM Taq has replied

Replies to this message:
 Message 98 by Tanypteryx, posted 03-08-2023 1:06 PM sensei has replied
 Message 100 by Taq, posted 03-09-2023 12:33 PM sensei has replied

  
sensei
Member (Idle past 137 days)
Posts: 482
Joined: 01-24-2023


Message 99 of 106 (908155)
03-09-2023 4:16 AM
Reply to: Message 98 by Tanypteryx
03-08-2023 1:06 PM


I'm showing the data from the model. We can use it for whatever.
One of the things that I see is that under this model, in very large populations, practically none of the "neutral" DNA is fixed (at 0 or 1).
The gray lines in the graphs are actually more precisely for generations 1, 3, 7, 15, 31, 63 (2^n - 1).
What possible predictions do you think we can make from here?

This message is a reply to:
 Message 98 by Tanypteryx, posted 03-08-2023 1:06 PM Tanypteryx has replied

Replies to this message:
 Message 101 by Tanypteryx, posted 03-09-2023 12:49 PM sensei has not replied

  
sensei
Member (Idle past 137 days)
Posts: 482
Joined: 01-24-2023


Message 102 of 106 (908231)
03-09-2023 1:34 PM
Reply to: Message 100 by Taq
03-09-2023 12:33 PM


Do you see images or links to images now?
I described the model simplifications that I used.
Starting from a fixed DNA base, it takes millions of generations to reach equilibrium.
Depending on how much of DNA is junk or neutral, comparing DNA of two individuals and finding 99.9% similarity, seems very high, compared to my model for such large population.
Is it because we are still far from equilibrium?

This message is a reply to:
 Message 100 by Taq, posted 03-09-2023 12:33 PM Taq has replied

Replies to this message:
 Message 103 by Taq, posted 03-09-2023 1:46 PM sensei has replied

  
Newer Topic | Older Topic
Jump to:


Copyright 2001-2023 by EvC Forum, All Rights Reserved

™ Version 4.2
Innovative software from Qwixotic © 2024