The best way to include fossils in the 'tree of life'

The researchers from the Bristol Palaeobiology Group, part of the School of Earth Sciences, studied the best way to understand relationships of extinct animals to other extinct species as well as those alive today.

The team's paper, published today in Proceedings of the Royal Society B, clarifies the most effective way to look at evolutionary relationships in the fossil record, and application of this method could change the way we look at the history of life.

Lead researcher Dr Mark Puttick from the Natural History Museum and University of Bristol explained: "When a new fossil species is discovered we naturally want to know where it fits in the tree of life.

"Our results show that the default method that has been used to do this for the past few decades is not always accurate, and so re-analysis with better approaches could lead to profoundly different conclusions about how we see the evolutionary history."

The relationships of are understood by studying their similarities and differences in their fossilised skeletons.

The most-widely used method called parsimony produces family by minimising the relative number of skeletal differences between species to group animals into nested groups - the closer the grouping, the closer the relationship.

The idea of parsimony is based upon 'Occam's Razor' - a long-standing principle that suggests the likeliest series of events is the one that involves the fewest possible changes and that no more assumptions should be made than are necessary.

However, the team has shown methods that model the process of evolution, rather than assuming the fewest possible changes, gives more accurate results than parsimony. This suggests the 'Occam's Razor' approach of parsimony should not be used to place fossils into the tree of life.

Dr Puttick added: "Some relationships we know from the tree of life will not change when using different methods: we know for a fact birds are descended from dinosaurs, but some relationships in the tree of life are less well known.

"For example, we do not know for sure what fossil is closest to the first dinosaur - and it is in these areas more accurate methods can change our perception of the tree of life."

Joe O'Reilly, also a lead researcher, added: "These findings may change the way we view key episodes in the evolution of life. We can ask exciting questions such as 'what was the first mammal' and be more confident in our conclusions by knowing we are applying the best models we have.

"Parsimony has been the main method to understand the relationships of fossils for the past 30 years, and thus some of our understanding of the tree of may be subject to change."

Co-author Professor Phil Donoghue said: "Our understanding of the relationships between extant species has been revolutionised in the last 20 years by modelling the realistic process of evolution, and not assuming evolution proceeds by the fewest number of changes possible.

"We show that palaeontology needs to take the same approach, and we identify the modelling methods that should become the default for the future."


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More information: Uncertain-tree: discriminating among competing approaches to the phylogenetic analysis of phenotype data, Proceedings of the Royal Society B, rspb.royalsocietypublishing.or … .1098/rspb.2016.2290
Citation: The best way to include fossils in the 'tree of life' (2017, January 10) retrieved 25 June 2019 from https://phys.org/news/2017-01-fossils-tree-life.html
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Jan 11, 2017
This whole exercise presupposes that the evolutionary myth is true.
Unless and until people have their eyes opened [or their fears of ridicule dropped] they will contiinue to struggle with this exercise in futility.

Firstly, abiogenesis is impossible - unless one changes the way basic physics and chemistry works. There is no way that purely naturalistic/materialistic processes can produce the abstract information component that governs life as we know it.
Secondly, the same informational requirement makes Darwinian evolution impossible.
Just for instance - one of the most basic requirements for multi-cellular living organisms is that the cell be able to replicate itself. Yet this very act is so incredibly complex that it could not have "evolved" from the first living "ancestor" [ based on the generous allowance that non-life could turn into life in the first place ].
Darwinian evolution is basically a god of the gaps where no other explanation suffices.

Jan 11, 2017
Fred the godlover believes that merely declaring something makes it true. He learned this from Genesis.

I know fred - it SHOULD be that easy - but it's not. Among other things, your god created hard work. That was his greatest insult. And yes I also know that original sin made it our fault.

Jan 11, 2017
Fred---you hit the nail on the head. I am waiting for true scientists to engage your comments in a scientific way.

The non-scientists on this column will react by name-calling, or trying to change subjects, or insulting, etc, just as Ghost has above. You know they have already lost the debate when they resort to such tactics.

Jan 11, 2017
Firstly, abiogenesis is impossible - unless one changes the way basic physics and chemistry works.
Secondly, the same informational requirement makes Darwinian evolution impossible.


...but you have no issue with your creation myth ignoring those confines?

Back to my nap.

Jan 11, 2017
Fred---I would add that it is important also for single-cell organisms to be able to replicate.

Anyway, true scientists will gladly listen to ideas that challenge their beliefs, and look into them to see if they are true or not. When people choose instead to plug their ears, you know they are taking off their science hat, and putting on their blind belief hat.


Jan 11, 2017
The "Tree of Life" is an amazing puzzle. Scientists have tried to put together a category of life in taxonomy and lable them in species, genus, family etc ranks. Those closer to each other are supposed to be closer related. Evolutionists also try to show an order of how life forms evolved in billions of years.

When you consider a simple objective comparison of life forms such as the number of chromosomes for each, there should be an obvious correlation for species that are supposedly more similar to each other. However, what we see is massive randomness, and many species of each genus can have vast differences in number of chromosomes.

This puts a huge question mark on the supposed tree of life.


Jan 11, 2017
Firstly, abiogenesis is impossible

And you think it is impossible because...? Basic chemistry/physics does not forbid it in any way.

Also note - as has been explained to you a fair amount of times - abiogenesis is not part of the theory of evolution.

I am waiting for true scientists to engage your comments in a scientific way.

Unsubstantiated declarations of faith can't be adressed scientifically. The evidence is all there (e.g. in the fossil record) . All he and you do is say "I don't believe it". That's not an argument. That's just willful ingorance. There's nothing to debate.

Anyway, true scientists will gladly listen to ideas that challenge their beliefs,

Scientists have no beliefs. That's the entire point of doing science. You do work that stands on its own. Others can evaluate it without needing to believe in anything.

Only religious people can have beliefs challenged. Since only they take up baseless drivel and believe in it.

Jan 11, 2017
Anti,

Unsubstantiated declarations of faith can't be adressed scientifically.

What are you referring to?

The evidence is all there (e.g. in the fossil record) .

What evidence are you referring to? And what do you mean by all? Can you be specific?

There's nothing to debate.

Says the non-scientist. There are many comments above that you could engage in debate.

Scientists have no beliefs....

I think that is your funniest line yet! Of course it is totally false. Scientists have many beliefs. So do you. To deny it is dishonest.


Jan 11, 2017

The non-scientists on this column will react by name-calling, or trying to change subjects, or insulting, etc, just as Ghost has above. You know they have already lost the debate when they resort to such tactics
Another voice from the choir.

And AGAIN, just declaring victory does not mean you have won. You can't expect to get away with this just because god is on your side you know.

Jan 11, 2017
I think that is your funniest line yet! Of course it is totally false. Scientists have many beliefs. So do you. To deny it is dishonest
Godders fail to appreciate the difference between faith and confidence. Scientists develop confidence in their theories based on accumulating evidence.

Religionists develop their faith by refining their ability to ignore evidence.

This is always true even though it is not aways readily apparent.

Jan 11, 2017
Ghost, I know you are smarter than this, but I have to repeat what I stated above, becuase it is so applicable:

The non-scientists on this column will react by name-calling, or trying to change subjects, or insulting, etc, just as Ghost has above. You know they have already lost the debate when they resort to such tactics.


Jan 12, 2017
So, after a day, I find no scientists willing to engage in debate on this crucial topic. Only some off-topic comments by atheists. And a plugging of ears and a shutting of eyes. By self-professed scientists. That shows a sad state of science.

Jan 12, 2017

What are you referring to?

E.g.:
Fred: "There is no way that purely naturalistic/materialistic processes can produce the abstract information component that governs life as we know it."

This is a statement of belief without substantiation.

or this:
Bart: "However, what we see is massive randomness, and many species of each genus can have vast differences in number of chromosomes."

'Randomness' is a statememt of belief (i.e. not quantifiable). Why do you have a problem with different numbers of chromosomes? Chromosome numbers differ. So what?
What evidence are you referring to?

We have the fossil tree and we see how species changed over time to adapt to the environment and one another and how species split off. Go to any natural sciences museum. The evidence is right there. You can look at it yourself. No interpretation or belief necessary at all.

I think that is your funniest line yet!

Well, you don't know how scientist tick. Big surprise.

Jan 12, 2017
Ghost, I know you are smarter than this
Well I know I am smarter than YOU that's for sure haha.
The non-scientists on this column will react by name-calling, or trying to change subjects, or insulting, etc, just as Ghost has above. You know they have already lost the debate when they resort to such tactics
And you know lots of well-known scientists like Krauss and Tyson and Dawkins call you names as well.

But your book does all the name-calling for you, calling unbelievers blind and ignorant and wicked and of course evil, which is highly insulting don't you think?

It's the kind of insult that can and does get people killed.

So forgive me for using the kind of words that godders only imply because they lack the honesty to speak them.

Jan 12, 2017
So, after a day, I find no scientists willing to engage in debate on this crucial topic. Only some off-topic comments by atheists. And a plugging of ears and a shutting of eyes. By self-professed scientists. That shows a sad state of science
Real scientists are a minority here yes. But what makes you think they would want to tangle with you?

You guys don't debate, you preach. You dont reason, you declare. The only response you can expect is from people like me who choose to illuminate the fact.

Jan 13, 2017
Firstly, abiogenesis is impossible - unless one changes the way basic physics and chemistry works.

@FredJose - Not at all. Remember that what we call life is really nothing but a series of chemical reactions occurring in a bubble of lipids.
Secondly, the same informational requirement makes Darwinian evolution impossible.

@FredJose - But you consider the Invisible Man in the Sky to be a plausible explanation?
When people choose instead to plug their ears, you know they are taking off their science hat, and putting on their blind belief hat.

@Bart_A - Do you realize the extreme irony of using this statement to promote a religious viewpoint?

Jan 13, 2017
So, after a day, I find no scientists willing to engage in debate on this crucial topic.

At the multicellular-organism level, evolution by random mutation & natural selection generally takes a long time to produce noticeable effects. Consequently, it's easy for people to selectively blind themselves to the evidence and deny that it's happening. But at the microbiological level (full disclosure: I'm a microbiologist) - where generation times are measured in hours - it becomes glaringly obvious that evolution is A FACT.
We have the fossil tree and we see how species changed over time to adapt to the environment

@antialias_physorg - Not exactly accurate. The changes happened at random and the individuals whose changes happened to give them an advantage out-competed & out-reproduced the ones without those changes. Adaptation was a happy coincidence, not the reason for the changes.

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