So good afternoon. I wish I were able to do this in person, but obviously it goes without, then it wouldn't be safe.
Let me start by thanking returns and the organisers of this similar series for inviting me to share with you some of their research staff.
My group carries out we are based at the Department of Zoology and we examine senescence or agan, as it's often referred to as the Tree of Life.
And we do work with mathematics and ecological and evolutionary modelling quite a bit.
I've tried to tone that down a little bit for this presentation.
But obviously, if you've got questions about the stats or the maths, very happy to answer them.
Before I jump into it, I would like to reveal that, take a message, and that is that senescence or agent is not universal.
It does happen in humans, but we are amongst the very few species that can form an exception to the rule.
And this is big news because for a very long time, as you will see today,
senescence was believed to be universal, to be found no matter where you look at it.
And because it's a really old question, no pun intended,
I thought it will be fit in to start by showing you a piece of art that does the fountain of eternal youth.
I think that this really tabulates the main research that has been paying attention to the causes of ageing.
We biologists, medical scientists, evolutionary biologists all have been obsessed with trying to find where the fountain of eternal youth lies ahead.
And the myth behind this was that the lucky one to find it and to either base in it or to drink from it would show eternal youth,
which is formerly kind of a increase or least stability in your vital functions.
This is a little bit of a summary of the research that we conduct in my in my group and other than their words,
senescence from the Latin PSINet cheddar, which means to become decrepit, you'll find other words such as plants.
And so one other piece. One of the efforts I'm going to try to carry out today with with the audience
here is to emphasise the message that humans are not the centre of it all.
Obviously, we've got a strong emphasis in trying to prolong lifespan, in prolong health spun as well.
That is the use of good quality of life.
But we may learn one or two or more things by looking around and stop looking into our belly button to look for that fountain of eternal youth.
So this, in essence, is one of the oldest questions that philosophers and researchers have looked into.
The first written recording of senescence caused by two 350 B.C. and it was first formulated that we know of by.
Of course, of all our feltl who back in the day, apparently roads, attacks, saying that if you want to live long and prosper,
which of course, back in the day was no more than 35 to 40 years, keep that in perspective.
You would do well in going for long walks everyday and then not eating too much.
I'm going to touch on that. Not eating too much.
Later on in this talk, from our democratic perspectives, that is in terms of how individuals in a population may suffer or not from senescence.
So in essence, is define what happens between when you first become an adult, until when 99 percent of individuals in that cohorts die out.
So in a depiction, you can see senescence here.
You can see that fertility in blue is declining after a mean peak of reproduction with age, and that the risk of mortality,
that is the odds that you can survive to the next year, increased quite exponentially with age.
Of course, you can see that the mortality risk is quite high early on, but that's not what senescence is looking at.
Senescence is just looking at what happens between when you first become an adult until you die of.
So in essence, it's very important for many very reasons,
one of them is how old you are and what country your base and know what gender or what socio economic
background or what neighbourhood you live will affect how big a loan you can get from a bank.
And all of that is these are natural scientists, which predicts how likely you are to die if you are likely to die young than your requite,
unlikely to be able to return the bank loan and dangerous. So your interest will go higher.
But in a sense, it's also equally important for a species.
Hecker's, the tree of life, not just humans. Think about what you had for breakfast this morning.
You probably have some orange juice. You.
But I had some other fruits coming from the plank in them. Perhaps. Yes, for dinner as I did.
You had a lovely bottle of of French wine and productivity.
That is brought to you by the planking, them by the animal kingdom and other kingdoms can be affected by senescence.
If a suspicious and NASA very quickly chances that that species will remain productive.
That oranges or pineapples or whatever have you that you're eating, that will go down and you will not benefit from that much.
So how much and how long species live is key to the ecosystem services that species provide to us humans.
And he also has really important consequences for, again, back to we humans.
How long you leave, obviously, under what conditions you are going to be leaving, because then the years of health span and also importantly,
how long will society, the man that you work, not just in terms of years, but also how many hours per day, how many days per week, for instance?
Couple of years ago, a rather controversial but I think scientifically sounds pet was put forward by Professor Rejean Bob Bell,
the previous director of the Max Planck Institute for Demographic Research and one of my previous supervisors.
He had observed that longevity in Germany was really skyrocketing.
And as a consequence of that, he said, no, no paupers in compacting the working life to 40, 48 hours per week.
Instead of what he proposes, you know, working fewer hours, they work fewer hours per week, but work for longer.
So retire at the leisure time. You can imagine that was not very well received in the German media, but there you go.
The type of consequences and logical thought that underlines the prolongation
of lifespan in humans that we are currently witnessing in many countries,
not only Germany. What are the key question, since an essence, of course, is why does it happen?
Why have senescence evolved? No, I'm gonna point you out to this paper by method from 1990 and one guess in 1990 happened yesterday.
But in fact, it's 30 years ago now. Metaverse made a really nice review of how many theories have been put forward and tried
to define to understand what are the mechanisms for why senescence or ageing happen.
And at that point, 30 years ago, he counted 300 theories.
If you do the same exercise nowadays, you're much likely to find probably close to four digit numbers.
Still, in order to understand the main theories of senescence,
I thought that it will be interesting to just discuss them very briefly before we jump into into the research that I want to present today.
The first one is mutation accumulation. So the mutation accumulation theory states that organisms become more decrepit
simply because of all the mutations that can happen in your in your in your body.
Some of them will be deleterious. They will affect your performance negatively.
They will affect your fitness and their genetic machinery that we have evolved.
Now we have in place to try to fix two rebote or two, cancel out those negative mutations doesn't aren't fast enough.
So the rates of mutation of negative mutations is much higher than the rate at which we can fix them or NALDEN.
That's a consequence of that. Individuals that are lucky to get to live long.
Accumulate those mutations and therefore they become more kapit.
The second one is called antagonistic play chopping.
And this is a really interesting theory that has been proven to be true in quite a few animals humans.
Amongst them is based on the idea that genes can carry out more than just one function.
Those genes so-called play a tropic gene given gene can have a function early on in your life.
And the same gene can have a different function later on in your life.
It's been shown with evolutionary models that a gene that has a positive effect in your lifespan.
When you're young will be selected for by natural selection, even if the same gene has got negative effects on your fitness.
That in principle, natural selection should try to wipe out.
So one of the reasons why Antagonistically Trophy explains senescence evolve is if a gene has two functions.
One is positive early on, but negative later in life, the negative ones will become very much blind to natural selection.
And that's one of the reasons why and how Tennyson's can evolve.
The third mean classical theory of the evolution of senescence is that of that is possible soma and it is possible some of these mors organisms,
not plants. I will show you in a second. But most organisms can be broadly categorised into a germ line.
Namely, you're going to your reproductive organs and Soma needs some alone, which is everything Elaman,
everything else in your body that helps you meet and pass on your genes to the next generation.
Investments in energy, which is obviously a limited resource into Sohmer or into germ, is inefficient.
And as a consequence of the cumulative accumulation of these errors,
in terms of how energies accumulated through time, the individual tends to become less optimal than it ought to be.
If he had an effective machinery. So as a consequence of that, again, if you live long, you become more decrepit.
What's come into this three theories,
other than the fact that historically they've been very well accepted along the age in research and the age community?
Well, they all expect they'll predict that senescence is universal.
And against the backdrop of that is the fact that while we know that senescence has got a genetical a genetic basis,
here you have a study looking at what happens to the survivorship in the Y axis as a function of time or age in the x axis
of different cohorts of the same slide species for which one has been treated genetically to knock down a specific gene.
If you knock down a specific thing, you can see the bloodline cohort will get to the longer up to the age of 90 days instead of 80 days.
So senators that have a genetic basis, but it also has an environmental basis.
It also has an ecological basis where you live, where you eat,
where you hang out with kind of say how long and in what conditions you will get to this.
And one of the reasons or one of the ways in which that can be demonstrated is with calorie restriction theory are subtle.
I will remind you already pointed out to us that if you go for long walks and you don't eat too much, you'll get to live long.
If you watch how your diet or if you reduce the amount of calories that you intake,
if you restrain, if you restrict your calorie intake, you get to live longer.
This has been shown in mice. It has also been shown in flies.
It has been shown in bacteria as well. This field of calorie restriction, however, is a bit controversial.
There's been a few studies that have shown for the rhesus monkey that it either has no effect.
Or that he has a positive affect, so we can talk about that later, if you would like.
But the main thing is the understanding that genetics. That is nature and the environment nurture come together in almost like a
perfect marriage to shape the Age-Based trajectory of mortality and fertility.
Your fitness components, in other words. Still, this three theories, and particularly one of the fathers of these three theories.
Hamilton, they are so strong and they're so sure in their prediction that citizens should be universal.
That Hamilton back in 1966, published in a peer review manuscript.
Senescence is inevitable. It will be found even in the farthest reaches of the universe.
And the quote continues. Also observed, even in the most bizarre of creatures, ikaros the tree of Life.
Well, today I went to this. Wolf, back to you. Today, I want to show you that humans are not the rule.
I think many other aspects of science. So what it means is that this pattern that you can see here, which is what we humans follow,
increasing fertility and then a drastic decline in increases in mortality with age is not really what every creature across the tree of life.
Followups. We published a paper in Nature a few years ago where we show evidence for this.
There are some species that do follow the predictions on the evolution of innocence by Hamilton.
I'll give you some examples here, but I'll dive into them in a second. So you've got modern human populations such as Japanese.
You've got hunter gatherers and you've got other non-human species such as guppies and fulminates.
They do show an increase in mortality and declining fertility with age.
There are other species such as dimness firms like pine trees,
the Crookwell Dial and the Nine Crocodile and the Yellowbelly Marmot's in Yellowstone National Park U.S. were.
The increases in mortality do happen, but food safety also increases with age,
which is something that it's not predicted by a possible series of senescence.
Let's flip that around.
There are also other species like this, a tortoise, oh, it's brown algae in the intertidal of the Atlantic Ocean that show a decline in mortality.
We'll also have an increase in fertility as they grow older.
So what this means effectively is that there are some species where senescence not only does not happen.
Fitness component, which is what natural selection acts upon the other way, improve with age.
So just like a good bottle of French wine, the older the better.
If you're interested in the documents in that publication, you can take a look at that.
In the interest of time, I'm going to jump very quickly through this.
I will just mention that we looked at this paper in 48 different species and we found, in essence, is a second opinion.
Some species do on their goals in essence, and species don't. Some species have a flat projection of mortality risks and fertility to age.
And it takes all different kinds of combinations of fitness components.
So I'm just going to jump through all of this and I'm just going to make a call for how important it is to understand the mechanisms for a long time.
The fourth, on understanding the mechanisms has been placed on why we ask why humans finance.
And let us assume that everything else looks like a human mammals.
Birds sometimes will also sniff. But what we show in this paper is that we need to start thinking about how can the other species stop?
And specifically, even if he might sound like science fiction, what can we learn from them?
In order to prolong our lifespan and more importantly for long, our health span, the years of good quality of life.
So some of the approaches that we're taking my group are primarily inspired in three different pillars of science to tackle this question.
One has to do with using big data on the demography of multiple species in plants and animals.
The other one has to do with following individuals in their natural populations through a long time.
We've been following populations of birds, of trees, of fungi for up to 15 years now.
And another one has to do with understanding the molecular basis of why some species and they, in essence and other escape from it.
So I'm gonna tell you a brief overlook about how we're tackling this question from a big data point of view.
All this work is in a first instance, it was supported by the Max Planck Institute for Demographic Research, where I'm still affiliated.
And you've got there are photograph of the first group that started building databases, compadre,
which contains demography of plants and comadre, which contains demographic information for animals, humans included.
Back in Rostock, Germany. And this research is now based here in Europe and the Department of Social.
So what we have done in this project is for the last over 10 years, really, it's been it's been quite a few years now.
We have been following an archive in peer review publication that contains information on the demography that is their rates of survival.
The rates of development and the rates of reproduction of animals and plants.
Where you can see on the top left is a world map of the G.P.S. locations where the data were
collected by either researchers around the globe as well as by people in my group and myself.
Where you can see on the bottom is the amount of publications that contain demographic
information that we specifically target to address this question for plants and for animals.
You can see that it really has increase in a cumulative manner quite drastically.
So together we have got access to thousands of records on the natural population that I.
And the information about survival chances and reproductive rates of individuals in their natural environments.
The way in which this information is our taste, a matrix.
All right. And I promise that this will be perhaps the first or the second only time they'll talk about mathematics.
If you're interested in this model, I'm happy to talk with you later.
The main thrust of these models is the classified, the visuals in a population, according to some speech.
So how old you are is typically one of them. And in them, we track survival, development and reproduction from those.
We can then apply algorithms that we've been developing in my group and with some collaborators to precisely
look at the shape of mortality and fertility and to evaluate how many species do adhere to their prediction.
By Hamilton on Yes dude [INAUDIBLE] and arse. And which ones don't?
Now, when you're in grad school, the typically teach to the rule of one in a presentation.
The rule of one is thou shall only go and say thou shall only show figure with one main object in one's life.
Here I am breaking the rule of one big time. And the purpose of this is to try to overwhelm you, if I may.
With the amount of information that we have. Where you have here is I think it was three hundred and sixty.
Plant and animal species. Each little.
Each square has a collar.
In the background, the background has been classified according to the colour of the attacks on any groups to which that species belongs.
So you've got in light blue, for instance. You've got algae and turquoise.
You've got trees lighter too close. You've got palm in brown.
You've got mammals. And this graph is organised from the top left.
You can hopefully see an icon of a baby. And at the bottom right, you've got an icon of an elderly person.
So this graph is organised according to the chances that a species escapes from senescence on the left.
And in that continuum way increases the forces of mortality and declines fertility as it grows older.
And that's what it's meant by that old person.
I can see where you can see here is that there's a vast amount of variation in terms of the senators trajectories.
In fact, if we were to classify species according to black or white to you and there goes in essence or do you not undergoes an effort to get France?
In essence, what we find in this study is we know you go 307 species is 160 escape from Tennyson and 147 undergo senescence,
but they do so with different intensities.
So with a quick overview, you in big data for demographics, you can see that large amount of them if they don't undergo senescence.
Of course, in this graph, humans will be in the side that to other guys and.
I've made the claim that we can not only classify species according to whether they undergo Theravance or not,
but we can also measure just how hard they undergo.
And this is the second time where I'm going to be talking about some mathematical algorithm things as last time either way.
So we're going to use a metaphorical, if it is entropy, to classify when individuals die from the moment that they are born until they die.
You can picture on the y axis and survivorship of a cohort of 100 individuals.
What we're mission exactly is how quickly does that curve decline with age from
the age that Dana just begun mature until well under what we call in demography,
the wheel of death? Well, if this is the age at which in getting cohort, 99 percent of the individuals have died.
So because we start with 100 individuals, in this case, 99 individuals have died.
Well, you can see there is overall all this began three different types of curves of survivorship.
Type one. Type two, three. In fact, one. Most of the mortality event happened late in life.
That's where you see the decline of death. Right hand types in type two.
What you can see is that the loss of individuals, the rate of mortality is constant through time.
And in type three, all you can see is that the curve actually plateaus.
So as you get older and you're less likely to die. So the division between type two looking up in type two, looking down,
helps us understand how strongly do you see this or how strongly can you actually escape from senescence?
And that's the measurements that we have seen from this measure of entropy.
It's essentially correspond to a hedge value of minus one equals two one or a greater than one.
If this species finesses has negligible senescence, that is the performance of flat with age or if it escapes from senescence, respectively.
We can apply this measure if it is entropy across the tree of life now.
So we have got the information for different biological and taxonomic classes.
So on the bottom, you've got I've been up to Righi.
Those are bony fish you've got. And those are those are a coral.
You've got sacred sites. I got a fighter. Those are cycads by not today.
Those are pine trees. They're broadly categorised according to whether they belong to the animal kingdom in blue or to their plank in them in green.
And there are groups are going to those classes. Right. So if the bar crosses over there one line and it's significantly a bow,
then it means that that specific tax on a group overall escapes from senescence.
And if it's below, it undergoes or either evolved. Senescence may show you some of those examples.
So bony fish, bird plums, insects and mammals to which we humans belong have a strong propensity towards undergoing senescent rs2.
So flowering plants like money Magnoli oxidised.
There are other groups, for instance, like sponges and reptiles which belong to the animal kingdom, as you know.
And three other groups of the plank propensity to either have negligible senescence or to escape from senescence all together.
So in our exploration of what are the main drivers of senescence, one of the null hypothesis was will animals undergo senescence plans?
Don't. And what this graph shows is it's not that clear cut.
There are some examples of animals that escaped from senescence. And there are some examples of plants that do on their goals, in essence.
So it must be something different. Shall we continue walking through some of the mechanisms?
One of the most pervasive theories in demography and in life history theory is that of the fast flow continuum, the fast, slow continuum,
which is a theory put forward for us by the stern states that individuals allocate into reproduction or maintenance of themselves in a really,
well, tight and orchestrated Trade-Off. So a Trade-Off is by Gitari compromise.
So you've got six pots of energy and no more than that.
And you choose to either allocate everything to reproduction, everything to maintenance, or somewhere in the middle.
How much you allocate to each of those functions structures a continuum.
There are some species like C. elegans on the top left that allocates mostly to reproduction, very little to maintenance.
There are some other species like the one on the top, right.
Hunter gatherers and other human populations were most of the allocation of resources into maintenance.
And there are species in between. A colleague of mine showed.
If you understand where species are run across this continuum, which can be used through a proxy called generation time.
I'll define that in a second. You can predict whether the species has a high rate of senescence on the way axis or not.
So the species with a high generation time would be one that takes a long time to replace itself.
So creatures like Sequoia's creatures, like the bristlecone pine in the Dead Valley in the US,
which point since has a life expectancy of maximum life expectancy of over 5000 years.
Creatures like the Nile crocodile and to a lesser extent, creatures like you and me, humans tend to have a middle or a really high generation time.
Creatures like C. elegans or fruit flies bacteria might have a short generation.
So a species with a short generation time undergoes senescence much faster than species with a long generation time.
And you've got some depiction there of the species that Michael looked up. Yes.
And some really cute non-human animals as well. Well, as we interested in evaluating whether the Fast Logan team also applies to the plant kingdom,
as you know, the plant kingdom is another really diverse group of organisms,
and they deserve just as much attention in terms of our understanding of their biology as do humans and other non-human animals.
So, again, we've got a lot of information for the demography of hundreds, if not thousands of plant species.
We can derive from this demographic information, information about generation time, information about allocations into longevity,
like the rate of senescence or at the time at which individuals first become adults.
We can classify different moments of reproduction. We can explicitly look at how much individuals these every time that they reproduce.
So do we have one offspring or Talison? We're going to evaluate the degree or the frequency of reproduction.
That's the degree of either party or some species reproduce just once and then they die.
Other species reproduce quite a few times before they die.
We're going to value the reproductive output, which is the expected number of offspring to give a mother throughout her lifetime.
And we can also value the reproductive window, which is how long can you actually remain reproductively active?
And because we're also measuring plans were size.
It's a really good predictor of survival and reproduction.
We evaluated the rate of growth of each individual in the natural population as well as the rate of shrinkage.
And before I proceed, I want to take a second to explain what I mean by the rate of shrinkage.
I would assume that the audience that I'm speaking with today might not think
about how important size or loss of size is for the fitness of an individual.
Well, shrinkage, that is, the loss in biomass through time happens quite frequently in not just the plant kingdom.
Also in the animal kingdom, for instance,
there was a paper published in Nature a decade ago that evaluated changes in size in the Galapagos Island iguana.
It's been shown that the years following a La Nina event, it went to individuals that decrease in size have a higher chance of survival.
If you know anything about climate change and the media in that part of the world,
you'll know that when a media event happens, less food is available.
So what the researchers were able to found to find and what made this paper on Nature paper,
it was the Coplin of the fact that individuals that decrease in size more had a higher chance of survival.
They got to live longer. They postponed the onset of senescence as well.
So obviously, you don't tend to think of a shrinkage in humans other than when we go on a diet.
Right. But the type of diet, quote unquote, that these iguanas are able to undergo is quite drastic.
The ways in which signs were measured in this iguana is the length from this now.
That's the tip of the the face of the Delta reptile until the cloaca.
That's the organ that allows them to both defaecate and sexual intercourse with their authors.
We're able to measure is that distance and show that some individuals were shrinking by 20 percent in that length.
Now, can you imagine what it would mean for you to get 20 percent shorter from one year to the next?
Let that sink in for a second. How do you do that?
They're waiting was in which this one is were undergoing shrinkage, is by literally eating themselves inside.
They were exposed to low resources because of landing Evan.
And they started to restore to resource of the calcium that had been stored in their bones in order to be able to survive to the next year.
So one of the ways in which you can live longer is if you decrease in sight.
So in the blank in them, that also happens. They raise whether understanding the shrinkage can deviate predictions from
the Parslow continuum and the importance of generation time for senescence. It might seem that you have a better chance.
You have got a lot of roads. The roads could be maybe.
Information about human individual income and commerce could be different, vulnerable.
So you could halve anything that you look at maybe in blood samples, concentration of oxygen.
There could be any volume information about each human individual.
You've got you've got a data set that contains a thousand individual human records and then 10 Durrell's.
You might suspect that a lot of those variables may be correlated against each other in
such a way that if you want to understand what makes an individual healthy or unhealthy,
you ought to reduce all of that rich data.
Well that's what ipca the principal component analysis is, the statistical way, multivariate way to reduce dimensions in a data set.
So just like the example that I gave you in humans here, we've got a lot of different moments for demographic performance in plants.
So the first question was, let's see if we can reduce that according to the Fastenal Continuum.
If we did, you should find a single axis of variation where everything that has to do with investing on reproduction,
which in this graph is depicted in red, will be to one site.
So you look at lots of reproduction and everything that is related to survival, which is in grey and in black, that black is generation.
Time, by the way, will be to one site such a way that individuals or populations in this case, each point is one species will have to trade off.
They can see each other and only one axis will be important. That access is what we call before the fast flow continuum.
And here, well, you can see with plants, there's hundred in ten different species here, by the way,
is that the data are bit more dimensional, meaning the Fastenal continuum is not enough to explain.
The demography is a different plant species. There's something else going on here.
Well, you can find here is that little Greek symbol to the left in blue called Gunma.
That's growth. If individuals grow fast to the left did on these long, which is the value of our generation, time to the right.
There's a Trade-Off there that the fossil will. But every single moment of reproduction in the plant kingdom is decouple,
is independent or as we call it in that this is orthogonal to how long you live.
Every single arrow that is read has to do with different limits of reproduction and
they're running or someone else for that minute that whether a plunderer on their growth,
in essence or not, is probably not dictated by these trade-offs.
Well, you can see on the second axis is what we call the reproductive strategy,
its axis is that you absorb twenty one percent of that variance and it forms a compromise
between how long do you reproduce specious to the tub rupee's for a long time.
And how likely are you to undergo shrinkage? That's the Greek letter row at the bottom.
So it just again, two highlights. You've got individuals that grow very fast on the left or 18 high generation times and individuals
that have got high moments of reproduction under TARP or have the ability to decrease in size.
And together, these two axes explain about, well, close to 60 percent of the variance.
Now we can measure through very simple mathematics. How far away are the orientations of generation time from different moments of reproduction?
OK. So here you've got the degree of either party s. Here you've got the net reproductive output are not.
Which, by the way, is indeed the same term that epidemiologists use in reports of covenanted.
Where you can see here is another study that I published a few years ago in this case, 650 plant species.
Again, these are organised, according to the Fastenal Continuum, from left to right.
And the reproductive strategy is continuum from bottom to right.
Just as I show you before. Well, you can see is that on the third dimension, on foot in the forces of selection for or against mortality.
So Hamilton forces of selection states that they can come in three different flavours.
They can be confident with each. They can decline with age resulting in species on they're going senescence.
That corresponds to a negative slope. So a dog collar, a black collar on that graph to the right.
Or you can increase with age, therefore selecting for species that don't ever on their go senescence.
Disney Coplin that I mentioned before between the Fosco continuum,
not trailing off with reproductive strategies is necessary to predict whether our plant
species will undergo senescence towards the bottom left in black or we'll get from it or.
In Yellow Points. Just like we can do that for quite a few plant species, we can, and we have also done that for animal species, including in humans.
Because you're wondering, you human are here in the pink, not so.
You tend to live relatively long and you have somewhat narrow window of opportunity for reproduction compared to other organisms.
Both animals and very specifically also plants.
That slave is actually outdated, outdated. It says that this manuscript is in preparation.
It was it was published last year in Nature, Ecology and Evolution.
And then it's what we show is that just like it happens with plans to understand that demography is of different animals,
humans included, you need to understand their prostate gland, continue attributions.
And also how frequently do they reproduce? OK, so we know that the investment and the trade offs are important to understand.
In essence, I know not your question that you might want to ask is, OK.
So if a species that is really closely related to me undergoes senescence, I also likely to undergo senescence.
And the answer's no. By the way. So in this paper currently in review article you that there is what we did is
we evaluated whether the species on there once and essence for mortality in.
Right. Whether they had a constant rate of mortality with age.
In yellow or whether they escaped from senescence.
That is a declining mortality with age. And we've done this exercise for vertebrates and for invertebrates.
The expectation here was that the collars anchors these phylogeny,
which is a way to depict graphically how closely related you are to another species.
Those collars in the outer ring should be clustered. It's all the rights should be together.
All the blues should be together. All the yellows should be together.
But they are not so phylogeny. Our understanding of our sister species is not a good mechanism.
It's not a good mindset to predict senescence or its. We've also done the same analysis for plants and the same thing is true,
senescence is not explained by phylogenetic distance to assist our species within the animal or the plank in them.
Then what? What explains that? So we talked about trade-offs.
We know that some species and there goes and really strong trade offs such that if you locate a law into reproduction in red,
you cannot allocate a log into survival or generation time.
Ingrey, those species would be you and me, the rest of the mammal class.
In some it's. We can estimate the Orridge.
That is the strength of that Trade-Off.
We also know some other species like flowering plants, insects, reptiles and bony fish have got a slightly more soft and trails.
So when you do the SPCA analysis on this glass, the decoupling is not full, but it's green, not very strong.
And there are other species like dimness worm and the grasses where the decoupling is complete.
You can invest a lot into survival and a lot into reproduction.
We can then evaluate Kiritsis entropy that measure that mathematical measure of how lucky you are to escape or two on their growth,
in essence, to remind you if you're to the left of one.
You on their goals, in essence, if you are to the right of one, you escape from senescence.
So understanding how species. Suffer or benefit from the lack of trade-offs is key, a key predictor.
So when there's an Asian. There was indeed a paper put together by some of my collaborators in the Max
Planck that was calling for a more mechanistic understanding of senescence.
We now know that senescence is no universal. What's the next thing is, well, why do some species escape from it?
Where are they found both around the globe and across the tree of life?
And what makes them special is there's something that we can learn from them.
I'm to expose you're going I'm going to keep on pushing you guys to think about plants for a second.
The founding father of Modern Plants Ecology, John Harper, once said that plants are waiting out there waiting to be counted in content.
By the way, is the bread and butter of demography, too.
Each will take their licence if I'm allowed to odds in many other less kind of charismatic species like fungi, insect also within the animal kingdom.
And the list continues.
So I'm not going to talk about the second angle here in the interest of time, but I do want to talk about molecular mechanisms.
I want to talk about long term individual records. I will target, I mean, the following minutes to you guys about some of the molecular underpinnings.
Through this exercise with Big Data,
we've been able to identify and isolate some likely candidates around this periphery of cloud of data of species that have got,
quote unquote, altered demographic behaviours. If you remember, humans were more or less in the centre,
but there are a wealth of species that are situated around that cloud of what's possible demographically across the tree of life.
We've got some carnivorous plant species. We've got some orchids and other disciplines.
We've got some corals and sponges that we're currently studying in the Great Coral Reef in Australia.
We've got some birds that spend most of their lives.
Who knows? We're out in the sea in the league for a very long time.
So I want to talk to you about another plant species called Sistas. I'll do this or the Mediterranean rosebuds.
This is our plan that is found across the western end of the Mediterranean basin.
I've been following population that I mix of about 600 individuals of these endemic plant species
nearby Barcelona and these rather dramatic landscapes called Montserrat Mountain National Park.
Specifically, what I was interested in was to test the hypothesis of mutation and cumulation.
I'll remind you of mutation. Accumulation is one of the main theories of senescence.
And what it states is that, you know, goes in essence, you become more decrepit.
Your vital functions go down with age because you're stuck with deleterious mutations, negative mutations.
One of the ways with which some organisms like long live plants can get rid of mutated tissue is by shedding parts of their anatomy.
Obviously, you know that I'm gonna lose my way,
but if I cut your arm set on your right arm is full of mutations, which is compromising your performance.
So the whole individual that you are, if I cut it and I don't take it immediately, I don't take you immediately to the hospital.
You will die. However, the ability to cut modules and continue live in is quite common in other creatures.
Reptiles can do this. Plants do that as well. Very often.
So what I was interested in experimenting with is what happens if I cut off modules or plants and then I continue tracking them to time.
Will plants that have on their go forced shedding of modules in the bottom row
indicated with the Cesur have a higher rate of performance and lower rate of senescent?
Similarly, inspired by Aristotle's work, I wanted to test how likely you are to escape or it's on their growth,
in essence, if I give you less or more resources. So calorie restriction.
Now, obviously, I cannot physically put a plant on a diet in the field and do something of it in an easy way.
It's impossible to extract nutrients and minerals with the soil without destroying
the root system and therefore compromising the demography of the individual.
So instead of extracting resources to put the plan on a diet, what I did is I gave it more resources.
And in this ecosystem, the resource that limits the growth of the plant is phosphorus.
This is a phosphorus depleted soil.
So I gave 200 individuals of the of the population pockets of phosphorus so that they could take them from the resources of the roots.
And the expectation in this case is that by virtue of having more resources, they will live longer.
So they will be faster. And there was cineaste faster as well.
For each of these 600 individuals start in 2014 and still ongoing.
By the way, despite Korvettes within measuring the biochemical activity.
Of its performance within measuring the physiological activity of its performance and with a mission,
different rates of the demography of the individual survival grow the probability that each year the reproduce if the reproduce,
how many seats do they produce? If the seats are produce are how many embryos within each seed?
Are the embryos viable? Can they germinate? And do they recruit?
So just to give you the short of it, it's really hard work and it's work that happens in the summer under really hot Spanish sun.
Of course, too, sometimes 40 Celsius degrees for each of these individuals.
We have codebreakers of each. And their ways with which we can do that is by taking ventral ecological measurements.
So, as you know, some trees have the ability to keep a record of how much they're growing every year with the rings.
So ad hoc study. At the end of the study, we can take a subset of the individuals, age them,
counting the rings and associate where we have measured before to how old they were.
OK. So you're going to see here is for each of the functions, biochemistry.
Physiology and demography, whether the functions decline with age now will be represented with an old person,
I can inbreds whether the functions remain constant with age and that's Roob
a sentence with a black icon of medium age woman and whether the functions,
the vitality of those functions improve with age. And that's what we call negative senescence.
And that's represented with a green icon of a baby. So what you can see here is that's where they control individuals to which we have nothing.
We merely follow them through time. Some functions do decline with age.
Some functions stay the same and some functions improve with age,
such as the probability of reproduction and the number of seeds for the youth producing the flower.
Contrast that with what happens to individuals for which we had fores shedding.
So this worrying to me is where I cut a third of distance and I just waited for them to regrow them again.
Well, you can see here is that the probability of undergoing senescence goes on.
So this are more likely to either have negligible or in some cases negative citizens.
And last but not least, the individuals to which we gave additional resources, we had expected that they will undergo something faster.
But what we found, in fact, is that they don't. There were Harborough, the Delta, to have an increase in vitality in many functions.
They control individuals, did not. What was interesting to me from from from this analysis is that depending on what level of biological organisation,
the biochemistry and physiology or the demography, the signatures could be the couple.
You could be undergoing senescence at one level, but not the other.
And we would have expected four different levels of biological organisation to be coupled.
One after the other, such that the processes will upscale from fuselier.
So from biochemistry to fishier to demob theory predicts, we don't find that.
And talking about modularity, I want you to think of plans and many other organisms is like a pile of strops.
The main function of a plant such as this one.
Hopefully you can see that. So bio on the way a plant works whose.
It takes water and neutrons from the soil. It transports them in the vasculature.
You can think about them in terms of arteries. To the leaves. In the leaves.
The nutrients. The water will be transform into carbohydrates with the help of energy coming from the sun and oxygen, which is then reduced to CO2.
Right. There are ways in which those nutrients are transported from the ground up to the leaf is through a collection of pipes.
So a plant is nothing but a collection of pipes from which the leaves are sucking to take those resources up.
One of the things that we know is that different plants and different animals as well can have an ability to act more or less independent.
So you can take from one stroke, but not from the other. The independence between those strong results in a higher degree of modularity.
And the expectation here is that organisms that behave more independently may
be able to shed modules and maybe you'll able to optimise ageing trajectories.
OK. So we tested this hypothesis. We've got ways to assign a degree of modularity,
mainly by taking a cross-section of the plant or the animal and looking at how independent different modules within it are.
We can then, for the same species, estimate the rates of senescence and the short of it is.
We found that plans that are more molecule are planned to have got a higher degree of internal
independence escape from senescence likely driven through the ability to shed modules,
to shed units of their anatomy. When things get ugly, we try to do the sensing in animals and we failed miserably.
We didn't find any signature there. I've got some ideas as the way that could have happened and why.
But in the interest of time, I'm just gonna skip through this.
I'm just going to bring up your attention to the fact that a lot of creatures that perhaps you
don't think about in terms of being closely related to humans are involved in the animal kingdom,
sponges and corals and also insects, some of which are colonial.
And in fact, what they represent is just a collection of different units that are tightly synchronised.
It's been shown that insects, by the way, that have a strong sense of sociality, that build colonies live longer,
that insects have the same ecological conditions that don't that are completely in isolation.
So the sense of society, the sense of community,
the sense of integration is likely a cause that should be explored further if we are to prolong lifespan and health spent within human populations is
going to move to that is going to showcase the fact that we've got a lot of
different creatures that we're looking at doing still work in South Africa,
doing the work here in Oxford, looking at a calorie restriction with flatworms on the top left and going to read
exotic places like Australia to evaluate the role of modularity on senescence.
Take a message from the top. From this, I just want to close up Tennyson's is not common.
In fact, that argue is the exception Asias that most of the high quality data that we have is based on animals like us where senescence is a thing.
So in order to understand. Why and how you undergo senescence, we need to look at how organisms allocate resources into survival and reproduction.
Understanding the biochemistry is ultimately the holy grail of Asian research,
and very little research has been infected or perform under interface between biochemistry and the demography of the species.
The more should be should be implemented. And as I showed in their last part of this talk, Senator, is this really multifaceted, multifaceted?
This controls with genetics. It's also controlled through the environment. A key question here is understanding to what extent.
One can win over the other. What condition is there genetics more important than the environment when we know that?
And only one we know that will we be able to deliver the benefits of ageing research to human societies.
On that, I'd like to conclude to thank you for your time, and I'll be very happy to take questions.