Auto Scroll
Select text to annotate, Click play in YouTube to begin
okay um so we're almost uh five minutes past here so um i think we can go ahead and kick the webinar off um and hopefully more people can trickle in as we go along
um so hi everyone uh my name is pamela i'm a journal specialist here with frontiers in ecology and evolution um i'd like to welcome you all today to the second installment of our frontiers conversations webinar series
um here in printers in ecology and evolution so we have a really interesting talk today on major evolutionary transitions uh so we're really excited to have you all here with us and thank you so much for coming
so before we start um and in case you're not familiar with us already i just want to give you a brief overview of our journal so we are a multi-disciplinary journal that publishes peer-reviewed and fully open access research across a wide
variety of themes in ecology and evolution so as you can see on this slide we have several specialty sections ranging from behavioral and evolutionary ecology um to ecophysiology which is a brand new
section that we just launched in 2021 social evolution and urban ecology but please do feel free to send us a message if you have any questions about the journal or if you might be interested in working with us
um we'd love to hear from you we always love to get feedback and we'd love to have you as part of the frontiers family so please don't hesitate to get in touch please also be sure to visit our website which you can see linked on the slide and we'll also put a link down in the
chat for you guys as well and also please follow us on twitter so you can stay up to date with the latest research and also be notified of upcoming webinar events like these
so i would like to extend a huge huge thank you to our speakers today for joining us for the second ever frontiers conversations webinar here in the journal um we really appreciate you guys coming today and we're really really happy to
have you guys here so thank you um so our speakers today are peter nonax who is a professor um in the ecology and evolutionary biology department at ucla kayla denton who is a phd student in the
ecology and evolution program at stanford university and amanda robin who is also a phd student in the ecology and evolutionary biology department at ucla so before i hand things over to them i
just want to quickly say that this talk is being recorded and the video will be posted on youtube on the official frontiers youtube page afterwards so with this in mind please just check that your microphone
is muted and that your camera is off so this should be off by default but double check it um and with and we will also have a q a session um directly after the presentation so during the talk please feel free to
put your questions down in the q a box at the bottom of the zoom window and our speakers will be happy to answer those at the end so if we have time during the q a session afterwards we'll also open it up for a more open discussion where you can
use the raise hand function to ask your question directly so without further ado i'm going to pass things over to peter to get us started here thank you very much um so hopefully i'm
not muted but i will continue on uh more or less if if uh you if you want to sort of unspool let's see if you want to
unschool four billion years of evolution right from say the last universal common ancestor all the way potentially to to us uh what you would find in in that process is that there's
a lot of biological innovations most of them are kind of tweaks on the existing patterns that we see so they improve the organisms a little bit better to to deal with their environment and so on
but somewhere along that four billion years there are changes that are for lack of a better term kind of special in other words they they may reorganize uh the biological world in some
fundamental way and so a number of people again have then just looked at this sort of chain of evolution and say well where where did these special events occur and how did those special events
occur and really this whole thing was the most kind of uh best-known attempt at this was by maynard smith and says moray in
in a series of papers and a very influential book in sort of 1995 where they identified eight kind of events that that that really again changed the biological world in
in substantive ways and in ways that demanded some kind of closer inspection and understanding on how those changes actually occurred and so what i want to do here is sort of
just kind of abstract those eight into just simple categories and so on and i color coded them in a way that others have as well which is that
these eight uh changes all the way from from replicators grouping into cells into human beings and and what we've done can be thought of in in sort of two ways
one is that they are sort of fusions of lower level formerly independent individuals into an integrated higher level single individual so on so fusions
the others whoops i'm getting some feedback here i think the others uh the others are then uh uh what i call information so they're
new ways sorry my phone just gave an alert so yes uh fun finance zoom
so anyway what we sort of see is is that that they sort of fall into these two categories of fusions and information and so again you have an any number of biological innovations most of which
again improve the organism and a few really very special ones that that do special things so let's see as we go then over since 1995.
um uh people have obviously this attracted a lot of attention and people have been working on this idea of special events within evolutionary history and i'd just like to sort of point out two other
two other uh uh works by andrew burke in 2011 and then seth moray again in 2015 that kind of looked at that original list of eight and uh modified it to some extent in
some cases combining what were sort of previously thought of or looked at as as independent events into a single into a single sort of major evolutionary transition
or adding a few things like the evolution of plastids or in burke's case interspecific mutualism and perhaps removing something so burke didn't view humans as a major evolutionary transition
now what i hope you also can see here is that the lists as you move from left to right have gotten pinker in other words there's more emphasis on the the fusion aspect of major
evolutionary transitions and a little bit less on the question of an information change on information sort of leap and part of this i think is because obviously
there's other things going on in evolutionary biology and people are looking at these at these events and just a general question of the evolution of cooperation and group living
and in that uh i would sort of say that that dave queller and jones strassmann again sort of approached this these problems as to how you transition across social groups and
their emphasis or at least they put an emphasis on the idea of that one way you can look at groups is you can look at their relative similarity or genetic similarity
so groups can range from being you know entirely fraternal in which place we're looking at genetic clones all the way out to what might be called egalitarian
with unrelated individuals or even individuals from from from different species so in essence groups can be placed somewhere along this continuum of
similarity of identity from again completely identical to very very different fraternal to egalitarian now what they also then could do is say well
we could look at at these sort of transitions in a sort of a two-dimensional uh graph in a sense and so we can start out and say okay groups can have more or
less conflict within them and groups can have more or less cooperation occurring within them and so if they are
down here in the left hand lower quadrant you basically are looking at more or less individuals so competitors so conflict not so much cooperation
if you move to the right hand side you start to form simple groups again individuals may come together to reap certain benefits and these benefits can be as simple as sort of
a selfish herd reducing predator risk predation risk and so on so not necessarily a lot of overt cooperation not necessarily a lot of
conflict going on then as you move to the upper left-hand quadrant you have groups that are now societies in other words there there might be rules as to who belongs
to the group uh there might be more cooperation within that within that group but also more conflict in the sense that the cooperation is producing benefits
and there may be conflicts over who is required to actually produce the benefits and how those benefits are actually shared within that group and then finally
uh if you can reduce that conflict uh such that everyone everyone more or less cooperates and doesn't doesn't there's the in any senses conflict with each other you can
actually turn the group into or the society into a coherent uh single organism at which point you may go back and start the whole process again
so what kuller and strasman then basically were trying to kind of in a way define or look at was how you transition from being a group
to an actual individual organism so at what point at what point do the individuals sort of meld into something that you would call just one individual what they call
organismality and they listed uh a six six kind of things that you would expect to see in an organism uh that would that would define it as an organism and not as sort of a group of
cooperating individuals so this process was was looked at in again in more detail by andrew burke in this sort of wonderful
book in 2011 um again in in his case sort of to find a pathway through this diagram so again remember that you are looking at major
evolutionary transitions so one can start with the idea that initially what has to happen is individuals kind of have to tolerate each other so in other words competitors
have to be willing to form into those simple groups and those groups have to have some kind of benefit for their existence and continuance then berkshire said well the next step
in this transition is what can go from formation to maintenance so if you go from a simple group to society again there are there are rules there are maybe individuals that belong to certain
societies and rather than sort of a fission fusion kind of uh coming together going apart these societies maintain themselves these groups maintain themselves over
longer periods of time and there are more benefits and there may in fact be more conflicts that have to be worked out to keep the societies to maintain the societies
finally there would be the step into this group transformation again what what what kuala and strassmann might have called organismality so now that the groups subsume their kind of
individual goals into a collective goal for all of them and again the idea here is that that that one has to happen is conflict has to be somehow managed and reduced
such that the groups can actually transform into this coherent whole single individual and some of the key points in in in burke's sort of
pathway to to to transformation is that the first two steps are can truly be bidirectional in other words uh societies can go back to being simple groups and simple groups can go
back to being competitive just competitors so in other words those aren't sort of absorbing states but the argument is that once once you sort of get to that group transformation that last blue arrow you
have transformed in a way that it is hard or impossible to really go backwards and what burke argued is that that process those those various steps and
particularly that last transformative step is strongly driven often by inclusive fitness kin selection so in other words going back to that continuum
of the types of groups that they can form fraternal groups are much more likely to to transform into these higher level organisms than
uh egalitarian groups so what queller strassman burke and other people since then have sort of added is is you you take a look at these biological innovations and you try to understand the processes
of natural selection that produce major evolutionary transitions and in many cases this is thought again to be driven oftentimes by kin selection
and says marae then in 2015 sort of again put the focus on the process on the transition itself and less so on the actual effects in a broader sense
in the ecology as you call it the ecological theater or ecosystems so a major evolutionary transition is something that could happen within a species or within a clade and maybe or maybe not it has wider
ecosystem implications so as i said what about that importance of information which seems to have been sort of mostly ignored or
not ignored but just not not thought of as much as the fusion so eva yo blanca and and others have really again thought about that to really get major evolutionary transitions it's also
a question about information and so again if we want to go from something like a prokaryotic cell to a pod of killer whales
there has to be sort of increases in physiological morphological and in many cases behavioral complexity and all of these require say more knowledge or a diversity of
information and this information has to be stored and it has to be accessible to the organism as well so we can put this information into
various levels and so what we have done is we've kind of taken the the previous work by blanca and uh just taken it or added a little bit to the levels in our
own way so level one and level two would be really kind of in the genomes right what what can you what can you pack in terms of the number of genes dna or rna genomes
and epigenetic effects as well level three then is where you start to put information not in the genetic code not in the genome but in actually
what animals learn or behavioral so again you store it perhaps in brains for example and so you have individuals that can learn and you also have groups or cultures
that that can form with learned information that can be shared across individuals so now information is not simply what's inside of one's genome but also what is sort of stored in
various biological ways level four is what we can call as inscribed so in other words it can be two ways one is sort of iconic which you can think about as a um you
know a scent mark left by a wolf or a pheromone trail left by an ant a mark left in the environment that actually provides information to other individuals
more impactful though is what you sort of see on the screen which we can call instructional information so so symbolic representations of information
written languages uh you know computer computer codes and things like that so now information is can is for the first time sort of also stored not in sort of a biological setting but in
an abiotic setting and we add to to these four levels that were generally sort of described by iblanca a fifth level that i think is is fairly new in the world
which is what we call dark information it's not dark in the sense that it's evil in any way but it's dark in the sense that there are now computers and algorithms that are actually producing information
um completely abiotically in other words there's no biotic actor other than whoever made the computer program to actually generate that information so for example something like
facial recognition technologies we don't really know how the computers are making them work the only way we know that they work is by the fact that we can see that they work so artificial
intelligence and algorithms uh are a new way again of developing information that's usable for biological organisms and we'll come back and we'll talk a little bit more
about this so the second thing here in in that original sort of major evolutionary transition is certainly one can go back in that four
billion years of evolution and look at major events that are neither fusions nor information leap so they don't fit into any of the eight things that that were
mentioned initially or into the sort of categories of being a fusion or an increase in information and so again we can ask simply questions like how how does how does evolution make big organisms
how do you go from being something that's small to being large neither of those changes require necessarily a fusion kind of event or neither of those require sort of a new way
of storing or using information yet both of those can be very much um transformative ecosystem level effects and you can have others there's there's any number of things like transitions from
living in water to being terrestrial or back the other way all of these things again can have major ecosystem level effects and so this is this is not sort of a new
idea people have have have again thought about evolution for in in these kind of special events uh before actually maynard smith and says murray says
so huxley stebbins bonner and certainly a number of people uh all to the present day have also looked at what makes a major change in ecosystems and so in some
cases what you sort of see is you have the same the same kind of things that that uh maynard smith and says murray fusions and information leaps well some of those are are mentioned in in this sort of
framework again then there's those others that are you might just sort of say give competitive advantages to to to plays or species and have these larger ecosystem level
changes so here's where we come in this is this is uh the paper that we are working on for this uh special
research topic and listing all the authors on it it's been quite a cooperative uh egalitarian group working on this i would say um and so what what our intentions are
is to sort of combine these these two levels of approaches or two two approaches to two major events so the the maynard smith says murray uh burke kind of approach plus this
other thing that we now call major competitive transitions and there are five points that i think that i want to sort of emphasize as to what we're trying to accomplish here
first off we're we don't really want to change terminology so a met a major evolutionary transition has been pretty well defined by maynard smith and says murray as you know either a
fusion or an information lead let's keep it as such but again we can now bring in these other kind of changes that promote immediate advantages their major
competitive transitions and we just again for for simplicity sakes we can call them mechs mcts the third point and i think this is this is sort of the the really the focus of
where we're going with this is this idea of whether or not this transition is a species level effect or whether it's an ecosystem level effect so when why and how does a major system
transition so when does an ecosystem really change when does that happen and it can be again if you go back and sort of think about that that major evolutionary transitions or even
competitive transitions can produce successful organisms or clades without changing ecosystems in any sort of fundamental way and one place where we could really sort of see this
is let's consider the evolution of eukaryotes and within this what you sort of see is that for the first say 2 billion years of life on earth we have more or less
a prokaryotic world about 1.6 maybe even 1.8 billion years ago eukaryotes first appear but then for the next billion years and this has sort of been
uh termed the boring billion nothing much happens and then suddenly within 20 or 30 million years eukaryotes take off and you have the idiocarin and the cambrian
explosions and the world is completely different and never goes back to to the sort of the prokaryotic algal matte world so two things there right what made
eukaryotes uh change or or have the major system transition and why did they take a billion years to do that
so to answer those sort of questions what we're sort of saying now is our fourth point is that for something like eukaryotes and others where there is no immediate major system
transition we're really sort of saying is that they perhaps are critical to such a transition but not at the time necessarily that they have evolved so in essence we want to amp we want to bring in a new
term which we call facilitating evolutionary transition so it makes it is part of a major system transition but it clearly needs other
evolutionary events to go along with it and the final sort of point is that there are perhaps catalysts that are involved in this process and one of the major catalysts that may
have had effects throughout evolutionary history are viruses so viruses may have been key actors to help the transition from
rna to dna they may have uh produced or helped produce the nucleus in eukaryotes and we'll talk about a little bit later about the key role that viral genes play
in making sexual reproduction possible and even in placental mammals the evolution of a placenta so without viral genes being moved across
horizontally species some of these major transitions could never have happened so now we have sort of the complete integrated process of of our diagram and again the question
that we're really focusing on oftentimes is that last one yes when how and why do we get to a major system transition and how do nets mechs uh
fets and catalysts all play a role in these various transitions and so we can look at a list of eight that was originally in the 95 list
and we can go through this process for each of those and obviously for for time limitations we're only going to consider three particular ones to sort of show
how we're thinking about this in terms of this somewhat more complicated diagram of interactions between various things and at this point i will transition control to kayla
who will talk about eukaryotes okay i just um requested oh perfect um okay so yeah i will be talking about the
transition from prokaryotes to eukaryotes and i'll be going through that diagram that peter just showed starting at the top with the new biological innovation in the case of prokaryotes to eukaryotes
there are multiple distinct new biological innovations including the acquisition of the mitochondria nuclei and diploidy among others
and these innovations arose so close together in time that it's actually unclear which was first second and third and the degree to which one might have facilitated the success
of another in order to go to the next part of the diagram with the major evolutionary transition and major competitive transition we can ask what was the process
that gave rise to these innovations and what was the consequence of these innovations so the process that gave rise to the mitochondria was a fusion between two previously
independent entities the one that became the mitochondria was a relative of alpha proteobacteria and this was the endosymbiont and then the host cell was probably an archaeon
so this was an endosymbiosis fusion event similarly for the nucleus endosymbiosis is one proposed mechanism for its origin although there's much more debate about
the identities of the host cell and the endosymbiont another proposed hypothesis is autokaryogenesis where the nucleus formed from inner imaginations of the membrane of a
prokaryote which also gave rise to the endoplasmic reticulum and finally the inside out hypothesis by bomb and bomb in 2014 is basically
kind of like the opposite where extracellular protrusions were extruded by a cell which that inner cell became the nucleus and those protrusions became the endomembrane
system and finally the process that gave rise to diploidy may have been a fusion between two haploids or endo replication the doubling of the genome
so ultimately looking at these processes we can safely conclude that the evolution of eukaryotes is a major evolutionary transition because it involved at least one obvious fusion which was the
mitochondrial acquisition and possibly others so there's a new integrated organism formed through the fusion of two previously independent ones
whether or not eukaryotes also qualify as a major competitive transition depends on the consequences of these different innovations so for um the mitochondria as we probably all know
it's the powerhouse of the cell so it increases the energy supply and there's even debate about whether this increase in energy actually predated and enabled phagocytosis although others say that phagocytosis
might be the process that gave rise to the acquisition so there's lots of debate about that as for the nucleus the pro the consequence one major advantage is the physical separation
of translation from the much much slower process of splicing and it's been suggested that eukaryotic gene regulation through the use of introns would be actually
completely impossible without this physical separation and finally for diploidy there's lots of different advantages including repair of damaged dna compensation
of deleterious mutations on one chromosome with a functional copy on another and when you include sexual reproduction there's tons of other potential benefits ultimately
whether or not these all these benefits were enough to qualify eukaryotes as a major competitive transition is something that remains unknown because
although we can say what they are doing now it's hard to know what were those initial advantages a billion years ago so it is possible that eukaryotes are both
uh met and uh meched now going on to whether they had a broad ecosystem level change peter already mentioned the answer is no
eukaryotes arose um about a billion years before the next broad irreversible significant ecosystem level change that being the cambrian explosion
so eukaryotes were necessary for this ecosystem level change because these organisms in the cambrian were eukaryotes but they were insufficient alone to have produced it
eukaryotes needed all these other different innovations such as an increase in the genome size or informational content um sexual reproduction
multicellularity exoskeletons neurons and lots more um so the answer here would be no eukaryotes didn't alone give rise to a
major system transition but they did play a vital role and therefore they do qualify as a facilitating evolutionary transition or fat
finally looking at the cambrian which is the major system transition i've talked to you about eukaryotes but there are so many other um relevant components
and i will now pass it over to to peter to talk about sexual reproduction as well as anisogamy let me just okay
i think you have to request access yeah i got it i think so sex in fact uh is
in our opinion very much a major system transition there's uh there is a lot of ecosystems that are dependent uh on sexually reproducing organisms
so again we can think about sex as as through this diagram as being sort of really an exemplar of how all of these factors have to come together to produce this this major system transition that
we're sort of talking about here and so again we can think about all the things that had to happen for biotic sex to really take off and and exist so all again the the major evolutionary
transition part of it is that that once you have meiotic sex you have all the populations level one and two information available to descendants so even though i don't have access to every
other human gene in the population my offspring my kids my grandkids and and so on might in fact be able to to access all the genes in the population and so
selection as as eva blanco has pointed out is is goes back to genes and not genomes as the unit of selection information management again that
ability to sort of uh rapidly combine good mutations and limit bad mutations is one of the things that that biotic sex gives you as an as a competitive advantage um
and so if we're being attacked by an asexual pathogen that that pathogen literally has to compete against the population's entire genomic diversity uh over time and so
offspring clearly are the fusions of two separate individuals so so no longer clonal reproduction there are fusions and again that that sort of fits in the net
uh meiosis with diploidy creates uh new forms of natural selection such as intragenomic selection so you can actually have parentally imprinted genes to affect
development and behavior and other kinds of features selfish dna uh increases genome size and information content so again not necessarily directly but it can move genes around
and as as kayla pointed out one of the big differences between eukaryotes and prokaryotes is the size of their genomes anisogamy the evolution of egg and sperm
is the the basis the original creation for sexual selection which obviously does not exist [Music] in clonal populations and finally i
would argue that meiosis greatly expands the range at which king selection can can occur and in fact i would sort of argue that that until you get mionic sex you can more or less explain all of
evolutionary biology without referring very much to inclusive fitness or can selection arguments but once you have meiotic sex then can selection really is very important to understand
about evolutionary processes and that i think is is a key point that sometimes is missed is that the that these kind of uh major evolutionary events aren't
necessarily always just driven by natural selection but they feed back to effect natural selection they change the fitness landscape of selection so again you can sort of
think about that as an mst feedback loop so that the met or the neck the behavior morphological innovation creates in the case of meiotic sex it
creates intergenomic kind of selection processes it creates sexual selection and it greatly affects or increases sort of the the purchase or the ability of kin selection
to then feed back on more or later morphological innovations so it creates a feedback loop within the process itself
so we have that change in the landscape of fitness selection going on all with the with the appearance of meiotic sex now as kayla also pointed out is that
there are three separate sort of morphological things that are occurring here and all of these are are really essential for for sexual reproduction and not all three of them
could have occurred or been driven by the same process in other words they must have occurred for their own particular advantages at particular times so diploid anisogamy and the general sort of
a size increase in genomes and information content so we can think of those as being individual mechs or mets that are fats in other words uh none of none of those three by
themselves could have created this this this major system transition all three were required and the final point i would say is bringing back our
our little favorite viruses so what do viruses have to do with myotic sex well it turns out again is that that sperm doesn't sort of just drill through
the egg and get into it sperm and egg fuse also in placental development you also have a lot of cellular fusion so in other words the membranes are fusing
and that is exactly what viruses do to enter cells and so there are specific proteins uh called fusexins produced by fusitive genes that that
facilitate this process of membrane fusion and if you look at the genomes of eukaryotes and the genomes of placental mammals you'll see that the genes that produce these
proteins probably the best explanation for their origin in these groups is horizontal gene transmission from viruses so without
virus genes there could be no fusion of sperm and egg membranes and without be able to ability to have cells fuse obviously sexual
reproduction in and of itself uh is not possible so in essence a meiotic sex is kind of the the fully integrated major system transition
with with a variety of mets a variety of necks important catalytic actors and changes again in the fitness landscape of selection
and so i will end that section and now transfer control for the final thing that we want to cover is human evolution and our humans
a messed which we think they are and i will seed control to amanda to discuss human evolution
thanks peter oops sorry about that so for the last part of the webinar we want to focus on how humans fit into our category goal framework here and we'll use this figure as a roadmap
starting with the center section looking that looks at how events that affect the species and clay level and so what stands out here for humans is our
complex spoken language which greatly enhances our communication and has long been thought of as a met due to leaps in the way that we transmit information between individuals
but this met really wouldn't have been possible without a major competitive transition so the specific regions in the brain that are associated with greater cognition and language ability
and also our larger brain size which is correlated with functionality and our spoken language allows human societies to gather greater amounts of level 3 or learned
information than would ever be possible within any one individual's lifetime and this really turns up the dial on the magnitude at which cultural evolution affects us as a
species and allows us to adapt and construct our environments in different ways cultural innovations are also not dependent on random beneficial mutations but can
arise intentionally and this has major impacts for how quickly and at what level we can affect our ecosystems
so when we come back to the figure and we've layered on complex spoken language now we can look at the level of ecosystem change that's occurred because of this and see if it's enough to bring
us to a major systems transition and here we argue that the answer is no if we would have just stopped at spoken language our global impact would never have reached the level
that it takes to drive an mst but we do argue that this spoken language was actually a facilitating evolutionary transition for events that directly paved the way
for an mst so human spoken language is a facilitating transition for symbolic representation of instructional information so the met and the mechd that make up
complex spoken language are actually a fit for being able to write things down and being able to write things down onto abiotic mediums allows us to increase the amount of information that
we can store the accuracy of the stored information and the efficiency of transmission and this has an especially high impact for oblique transmission because
being able to inscribe information can potentially immortalize it and then individuals far in the future can build upon it and so being able to build upon
uh generations of information through symbolic representation of language is really a key for the expansion of technological innovations that have expanded the realized niche of humans so
we have spread across every continent made major impacts on most ecosystems and a part of what has allowed us to do this is the technology that we've designed uh based upon large amounts of
inscribed language and some of these technologies actually allow us to manipulate or avoid the processes of natural selection and some of the those examples are listed here
and so when we go back to our figure and layer on the potential to inscribe language and then re-look at ecosystem level changes we think that here due to due to the
technological innovations and global expansion that's come with being the only species to store this much level three information that the answer is now yes
and when an mst occurs the context in which this entire cycle takes place completely shifts because now the global ecosystem is playing by a modified set of rules that are
set forth by the mst so this brings us to the question are humans the last mst or are there other mets and mechs forthcoming that will drive a new
major systems transition and two one way to explore these questions is to look at how information has changed due to the human mst and one way that it's changed is the
emergence of a fifth level of information dark information which peter talked about before is info that is generated by abiotic computer software and so this information level is only
possible from inscribed language and the technological innovations that that gave rise to that now can generate this kind of information
and there's two key components to dark information one is that it's produced by computer software with no direct human involvement and the second is that from the processes of
input to generated output can't be replicated or feasibly derived by humans so it's inherently dark even if some of the output were able to apply to real world problems
and so this kind of uh information is gaining traction so unsupervised machine learning algorithms are becoming increasingly capable of generating novel algorithms without added human input and
so here are some of the ways that we're currently applying this technology and we it's still in its infancy so we're likely far away from seeing a met where direct information is involved but
this does have the potential for in the future um helping keep humans alive on earth or expanding our niche even further and maybe far down the line seeing something like a
dependence or an inter mutualistic inter-specific mutualism met between biotic life and abiotic technology and so with that we would really like to encourage
folks to submit their own work on these topics and i'm going to pass it back to pamela
now to open us up to questions okay uh so thank you guys so much for that really fascinating talk um so i think in the interest of time we
can go ahead and jump into um any questions uh that people might have so let me just pull up the chat here okay so i think our first
question is from uh dan mcshee so he said thinking about the great oxygen revolution two billion years ago am i right that you would not say this wasn't was the result of any major transition in evolution
if that's right then there is no necessary relationship between mtes and major ecological transitions you can have an mte without an mst and an mst without an mte
um yeah i think i think the answer the answer is yes generally so again for for obviously for for some time constraints uh the great oxygenation event could be
certainly looked at as again as an abiotic catalyst something that that for example people have argued to guess that the multi-cellular high-energy lifestyles could not exist unless there was plenty of oxygen in the
environment so there again you could you could sort of say that the the plants the cyanobacteria whatever that oxygenated the environment was was facilitating
as a byproduct a later ability to have a major system transition but yes i think i think for us the the concepts of of matt and mech and again i think that
that's where we're trying to get a lot of this is at when when do they actually uh result in in these these more major ecosystem transitions and when are they
just sort of advantageous for the particular groups that they are and and don't have these sort of larger uh ecosystem transforming effects
thank you peter um so we don't currently have any additional questions in the chat so i'd like to encourage everyone if you do have a question to uh raise your hand i'm using the raise hand button on the bottom of the zoom window and then
we can unmute you and you can ask your question directly um if you do want to pop a question in the chat please also feel free to do so okay so we have a follow-up um comment from dan that says so do you
have a hypothesis for which uh for which what oh here we go in which msd will and will not require an mte
um gosh this is one this is a question i would almost like to sort of give to my my co-panelists here to to kayla and amanda i think we may we may all have our slightly different versions of what we
think um i yeah i i'm not sure that that i would be willing to sort of say i have i have a general hypothesis that would predict
when an mst would happen or not it's still kind of more more looking at seeing ones that have happened and trying to to decipher why they happened and why others
haven't happened so again so one of the things again that we we didn't present here is a a common map that just that is is set forth by by maynard smith and
others is sort of the evolution of you sociality for social insights i think it's arguable as to whether or not they actually have created a mess or will
create one or have any potential for any future major evolutionary transitions so i you know i think i think part of for me part of it is is looking
at each of these things and seeing well what's what's unique what's shared and i don't have like an overall sort of hypothesis that that i think fits across
every one of them so that's my view kayla um yeah i was gonna say that as for the conditions that will favor an mte or met um whichever um that would be the
fusions and the information leaps um and then as for which uh mtes will result in a major ecosystem transformation um i would say most
um with the exception of uh what peter mentioned use sociality um the first few major evolutionary transitions producing cells with chromosomes um eukaryotes
sex i believe are all critical components they aren't um sufficient to produce the mst but i think all of these are critical components of an eventual mst
and then the humans did create an mst so i would say that most but not all um our critical components but may not have directly
produced that uh thank you guys um dan i also just want to let you know that i did unmute you in case you are interested in chatting a little bit more about your questions so please feel free to do so
i don't want to um step in if there are other questions here i've got i've got another one if nobody else so we do have one question from the journal team actually then maybe we can circle back um to continue this uh discussion as well
so i have another question that says do these major transitions happen quickly or what controls their rates yeah that's a that's a good question and um
um we we amongst again sort of the the many co-authors here we batted that question back and forth and i think it's it it it has to some extent highly subjective as to what you think quick
means and so um i think we would all agree that that a billion years or more between the original appearance of eukaryotes and the cambrian
explosion is not quick um whether some of these other ones and again for exa for example the the evolution of myotic sex is
that there clearly have to have been multiple events each of which you know had to be advantageous in its own particular way
and they all seem to happen very similarly or very closely in time and the same sort of thing again for the the major features of the eukaryotic cell they all they all kind of have seemed to have
appeared almost simultaneously although no single simultaneous process could have could have produced all of them um so yeah that's i think i think when you
when you sort of get in to say well how how quickly does something happen and is that does that mean that that thing then was the major system transition or was it a fact because it required other things happen
is is still kind of to some extent in the subjective realm of trying to figure out what we mean by fast or slow and again kayla and amanda can can chime in on
we had we had a number of arguments and discussions about that when we were trying to put this all together uh thank you thank you peter um so i don't see any additional questions also if you want to circle back to um your follow-up question dan
please please feel free to do so okay um it also has to do with rates i guess so i wouldn't have put it that way an argument to be made and it's consistent with the data you with the
presentation that you've given us here today that there's been an acceleration the first major transition took a long time the next one took less time the next one took less time i date the origin of eusociality with
the origin of bryozoans um in the ordovician at 480 million years ago well before social insects but there's a point of view that says and i'm not saying this is mine there's a point of
view that says these things are awfully slow why hasn't anything happened lately really 400 million years since brya's owens and people is all that evolution has to show for it
why are these things so hard and if you follow that curve starting at the origin of life we should be at level 22 by now not level five or six yeah um so let me let me start off with
that but by one of the things that that's clear when you look when you look at say the list of what are called major evolutionary transitions is that some of them have happened many
many many times so if you if you are are okay with andrew burke's concluding of of intra intra-specific obligate mutualisms um those have independently evolved
maybe thousands or millions of times over evolutionary um um multicellularity has evolved multiple times again and so if if your fault
if you're following uh say say sesame ray's arguments to what a major evolutionary transition is and you sociality is is there isn't just one evolution of youth sociality there's multiple independent transitions in that
particular category and some of those have have occurred more recently i mean i don't know when naked mole rats cross that that uh transition and so on so some of those have happened more so and so
uh an interesting question again is is eukaryotes as far as we know have happened once humans have happened once and yeah they're they're they're the the the list if you go down that original
list um the the latest one is happening now right and the one before that happened you know many many million years ago the first sort of transition to use
sociality so yeah i think that that that that raises that raises the question of first off what do you what what do you actually define as as a matte event and
some seem to be just very very unlikely because they have happened only once and then again it seems like well have we talked out is there is there is there no future
transition possible now again and i think uh i i can toss this to manda a little bit is is uh if you expand your definition of what is alive to
abiotic machines to artificial intelligence then i think the next transition could be quite revolutionary in terms of melding biotic
organisms with abiotic organisms and the real question again not to get too far out here the real question is would abiotic organisms really need biotic organisms to have a
mutualism or can they go it alone so i don't know if amanda wants to to to talk a little bit about the future of maps i mean even if we don't go as far as to say that there's going
to be a melding event any new met or meched or any kind of major event that happens now is happening within the context of the human mst so everything that we've
done to the ecosystem and all of the cultural innovations and technical innovations that we pump out into the world so that couldn't have consequences for
how slowly or quickly just everything else can be how slowly or quickly evolution's affecting everything else and also the new kinds of things that can arise so that can have a consequence and then if
you do allow for the idea that technology could somehow affect or become a part of human
evolution in terms of how much we depend on it then that could be a whole different story and that will only get quicker as technology builds on itself i think i think amanda you've also you also pointed out that
fundamentally human humans are possibly the only organism in the history of planet that actually understands evolution that we can have a a webinar like this that talks about evolution which means
that in essence we can direct and change the processes of natural selection that that heretofore you know have been immune with with organisms literally deliberately affecting
how evolution happens and that that i think is is completely uncharted territory and and again the the the potential for that to change everything on the planet i
think is okay thank huge thanks guys so um we do have one more question uh from steven duplantier he says do we have to figure the really slow evolution of our kia in computing the
timeline of mets uh could you could you repeat that question one more time sorry um do we have to figure the really slow evolution of archaea and computing the
timeline of mbts um i don't know uh i i i would i would quickly sort of say is that that obviously what we sort of all realize is
that that mets do not imply you know necessarily better it just replies that there's there may be a new niche or new type of organism and so on so again if you
if you if you really want to look at the planet the most successful organisms on the planet are still probably bacteria in archaea right um so and and they may they may they've out
they've outlasted the dinosaurs and they maybe roll out last us so so you know simply because some clade is not a beneficiary
of a a major evolutionary transition doesn't in any way sort of imply it's less well adapted to whatever it does in fact i think it is fantastically adapted so so back
bacteria are bacteria and they've been bacteria for four billion years because it really works well um so yeah i i don't you know i don't know that lack
of a transition indicates anything other than fantastic adaptation peter okay so um we're now about 10 minutes over so i think um we can end the the question
um an extra session here but i just want to let you guys know if you do have a question and you didn't get the chance to ask your question um you can send us an email at ecology and evolution at frontierson.org so i'll also pop that in the chat for
you guys if you'd like to shoot us a message and get your question answered we're also going to upload this recording on youtube and you can post your question as a comment on the youtube video and our speakers have kindly agreed to
you um can i can i just say one more thing quickly which is that i think our our inability to give definitive answers to some of the questions that came up here is is
prima facie evidence for why more people could write papers to contribute to this sort of research topic is that i think i think if nothing else what are what
what we're trying to do is to have people raise more questions interesting questions rather than necessarily to to provide definitive answers so
again to the to to the to the level that we fail to answer your question that just proves how much we need you to write a paper that does answer the question better
oh and our emails are on the next slide if you want to i don't know who has the control of the slides right there yeah so feel free to email us awesome thank you guys um yeah so you
can also um email them directly of course and then also post your question as a comment on the youtube video so once that's available we'll send a message out to everyone um to all of our attendees so you can have the link
to the youtube video and so i think we can uh in the the webinar here then so thank you so much again to our speakers for joining us today is really excellent uh talk and discussion um and thank you to
all of our attendees so it's a real pleasure to have you guys with us today um and we hope that you will uh join us for the next frontiers conversations webinar so please do feel free to follow our twitter to stay
updated about that um and then on behalf of the frontiers and ecology and evolution team i just want to wish you all a great rest of your day so thank you
End of transcript