De-extinction and creating new life

[Albert VDS]

You have to consider that bringing back an animal and releasing it into the wild is like, for example, introducing rabbits in Australia back in the 18th century.

It didn't have a natural enemy so it's population could grow unhindered. This ever growing population is still a threat to crops and other vegetation.

The other thing to consider is that species disappeared because they couldn't survive in it's current environment, evolved into a different species or extinction either by natural events or humans.

All of which shouldn't be a reason to bring them back, unless can keep them from interacting with the current ecosystem i.e. put them in Zoos.

[SargeRho]

Every species is responsible for the extinction of at least one other species. The species it evolved from.

You have a poor understanding of how Evolution works.

[Klingon Admiral]

You have a poor understanding of how Evolution works.

Nope. A species will sooner or later produce mutations which are better at the niche the species inhabits than the curent dominant mutation. After a few sucessful generations( the number on which depends on whether the species in questions follows a k-strategy or a r-strategy) the mutation will be widespread enough that it's bearers will be able to out-compete the animals who do not posess it on a large scale. One could call this effect a critical mass of sorts.

And humanity is hardly the only species with reckless behaviour, in fact we are probably among the most sensible beings on this planet.

[KerikBalm]

Yes, you do have a poor understanding of evolution

"They had their chance at competing for survival and lost out. "

Often due to random events.

If you think we'd survive the events of the End-Permian extinction, you're very likely wrong.

So if we wouldn't survive random event X, and species A didn't survive random event X, why do we have more right to exist than species A?

Edited March 26, 2014 by KerikBalm
just adding more stuff without making another post

[Klingon Admiral]

Yes, you do have a poor understanding of evolution

You haven't told me why.

[KerikBalm]

because what you described is not speciation

all you described is an allele becoming more widespread

Moreover, when there is adaptive radiation, the "old species" doesn't go extinct.

When early lungfish like tetrapods started venturing on land, they didn't cause the aquatic Sarcopterygians to go extinct, did they?

Edited March 26, 2014 by KerikBalm

[Klingon Admiral]

A species is defined as a group of animals which can produce offspring which can also produce offpsring. Of course my example is woefully oversimplified, but after a set amount of alleles have become dominant, the animals poseesing that alleles will no longer be able to sucessfully reproduce with their ancestors a few to a lot generations ago. Every single species of living being, with the possible exception of homo sapiens, undergoes this process, has been for the last couple of million years and will continue to do so.

But still my fact stands, we can assume that every niche that is occupied by a species was already occupied by another species beforehand.

[SargeRho]

Why would humans be a possible exeption to that? We didn't evolve through any different means than other animals. Speciation doesn't automatically mean the original species goes extinct. Prime example? Humans. Or rather, Primates. If you were correct, there would only be humans. We wouldn't have Neanderthals, or for that matter, Gorillas, Chimpanzees and Orangutans.

[Red Iron Crown]

For that matter, if newly evolved species caused earlier species to go extinct there would only be one species on Earth.

SargeRho, I think Neanderthals are a bad example for the point you're trying to make.

[Klingon Admiral]

Home sapiens sapiens is the only species know which posesses a global population, which has eliminated all but the most extreme selection factors (at least in some parts), and everyone can relatively easy procreate with someone from the other end of the world. Alleles would have a very hard time to become dominant in current humanity. If we would have stayed confined to relatively small tribes for a couple more millenia, sure, Homo sapiens surely would have split. Luckily, we have averted that.

And what about the most recent common ancestor of homo sapiens and the neanderthal? He's not around anymore. And the notion that homo sapiens and homo neanderthalensis are two seperate species has become disputed recently, up to 20 to 30% of the genome of non-african humans may actually be neanderthal-genes. Which probably doesn't matter much as neaderthals and we were very, very identical, but interesting none the less. And the most recent common ancestor of the apes isn't around any more as well, probably because the apes we know today were better at being apes than their ancestors. And if the apes survive the whole anthropic mass extinction, they will make way for animals which are even better adapted to their ecological niche. That's a funny thing about evolution. Every species is the best at what it does but at the same time just barely good enough at it.

[CaptainKipard]

I think what the Klingon is trying to get at is that separate branches sometimes compete the way Homo Sapiens eradicated Homo Neanderthalensis, he's just expresing it poorly. So I think the correct way to say it would be that some phenotypes out-compete others.

Why should we bring back extinct species?

Because studying them can be useful to us. Scientists will always find ways to exploit nature for the benefit of hoomans. Dun Qapla'!

[KerikBalm]

Given data indicating interbreeding between neandertals and other humans (and also Denisovans), their lineage continues.

It would help to define species... but thats another topic.

A species can split with no extinctions

A species can evolve without any branching, still with no extinctions - the only lineages going extinct are at the individual or small group level. The interbreeding population does not go extinct.

Even in the case of native americans and Europeans - native lineages continued on in many areas, although most often heavily diluted by European interbreeding (ex: sacajawea, or however it is spelled).

Lobe finned fish did not go extinct, they branched - one branch was the tetrapods, they did not go extinct, they branched - one branch was the amniotes, they did not go extinct - one branch was the synapsids, they did not go extinct (although they nearly did at the end permian and mid triassic).... and so on.

When amniotes split into diapsids and synapsids, both lineages continued.

Of course some species cause others to go extinct, but this concept of making the "ancestral species" going extinct is flawed IMO.

The "ancestral form" may go extinct, but the population continued - and of course there are plenty of examples of the ancestral form continuing with little change while a new branch takes a very different form.

But still no answer to my previous statement (I know, I added it in during an edit, I started the edit before there was any reply):

If you think we'd survive the events of the End-Permian extinction, you're very likely wrong.

So if we wouldn't survive random event X, and species A didn't survive random event X, why do we have more right to exist than species A?

[Klingon Admiral]

I think what the Klingon is trying to get at is that separate branches sometimes compete the way Homo Sapiens eradicated Homo Neanderthalensis, he's just expresing it poorly. So I think the correct way to say it would be that some phenotypes out-compete others.

Recent research indicates that the Neanderthal did not exactly went extinct, but that significant interbreeding between homo sapiens (sapiens) and home (sapiens) neanderthalensis did take place and that they were, at least partially, absorbed into the modern human race. In that case, the seperation of the modern human and the neanderthal in two seperate species cannot hold up. Other than that, yes. Just ask the dicynodonts about that punkish upstarts called dinosaurs.

Because studying them can be useful to us. Scientists will always find ways to exploit nature for the benefit of hoomans. Dun Qapla'!

Well, we could probably bring back things like the Aurochs, maybe even the Mammoth, but probably not much more. Then again, isn't our cattle just a whole bunch of phenotypes of the Aurochs? And Mammots are a sister taxon of the asian elephant, we could just study these and then make some very educated guesses. Above that, we will run into serious problems.

[CaptainKipard]

Well, we could probably bring back things like the Aurochs, maybe even the Mammoth, but probably not much more. Then again, isn't our cattle just a whole bunch of phenotypes of the Aurochs? And Mammots are a sister taxon of the asian elephant, we could just study these and then make some very educated guesses. Above that, we will run into serious problems.

I know what you're trying to say but even within what you would technically call a single species, there can be significant differences that can be studied and then exploited. I know of a few examples in our own species, so there's every reason to suspect there will be many in other species. Even if mammoths are just a subspecies, they can hold the potential for some interesting and useful science.

Edit:

Have a look at malaria resistance, bone density or muscle development. There are some interesting mutations that lead to these, that scientists wouldn't even know existed if they didn't manifest as a new phenotype in our own species.

Edited March 26, 2014 by Cpt. Kipard

[Kryten]

Every species is responsible for the extinction of at least one other species. The species it evolved from.

If this was true, 'if humans evolved from apes why are there still apes' would actually be a major problem.

Recent research indicates that the Neanderthal did not exactly went extinct, but that significant interbreeding between homo sapiens (sapiens) and home (sapiens) neanderthalensis did take place and that they were, at least partially, absorbed into the modern human race. In that case, the seperation of the modern human and the neanderthal in two seperate species cannot hold up.

If non-production of fertile hybrids was actually used to define species, we'd have maybe two species of small cat and three of canids. Your definition has not been seriously used in taxonomy for a long, long time.

Edited March 26, 2014 by Kryten

[CaptainKipard]

If non-production of fertile hybrids was actually used to define species, we'd have maybe two species of small cat and three of canids. Your definition has not been seriously used in taxonomy for a long, long time.

What are you talking about?

[Kryten]

What are you talking about?

He says that since neanderthals and cro-magnons interbred, they're not separate species. Except species are simply defined by a certain level of phenotypical difference, the same as taxa at all levels. This is why, say, domestic cats and asian leopard cats are classed within different genera-despite producing fertile offspring consistently enough for F2 hybrids to be commonly sold as pets.

[CaptainKipard]

He says that since neanderthals and cro-magnons interbred, they're not separate species.

Well that's not quite what he said, but ok.

Except species are simply defined by a certain level of phenotypical difference, the same as taxa at all levels. This is why, say, domestic cats and asian leopard cats are classed within different genera-despite producing fertile offspring consistently enough for F2 hybrids to be commonly sold as pets.

I had to double check because that didn't sound right to me and it turns out that the criteria for a species is unclear. You made it seem as if there's consensus. Let's not do that. AFAIK for most purposes interfertility is an adequate criterion for deciding species, so that would make all canis lupus the same species, and domestic dogs a subspecies or breeds. It would also clearly make neanderthals a subspecies of Homo Sapiens.

[Kryten]

You made it seem as if there's consensus. Let's not do that.

There is no consensus on a standard definition of species, true, but there is consensus the fertile hybrid definition doesn't work. Just look at cats again; as well as the ALC-domestic hybrids, we also have second generation domestic-seval, serval-caracal, and domestic-jungle cat hybrids. Care to find a single source that puts all of these in the same genus, never mind species?

That would make all canis lupus the same species, and domestic dogs a subspecies or breeds.

Canis includes more than C. lupus; C. lupus, ethipoian wolves, golden jackals, and coyotes can all interbreed to produce fertile offspring.

Edited March 26, 2014 by Kryten

[Red Iron Crown]

Is species somewhat like race in humans, then? It's more of an arbitrary definition than a precise genetic difference?

[Comrade Jenkens]

What I was taught was that two members of different species cannot interbreed to produce fertile offspring. However I admit that was during A levels and they do miss out detail during that part of education.

[Kryten]

It's really kind of a mess. The definition in actual use by taxonomical workers differs between the group being looked at; microbiologists use 97% or under similarity results from DNA hybridisation, which would put humans and chimps in the same species if applied to primates. In animal groups it is simply a certain level of phenotypical difference (that level differing between orders), be that difference morphological, behavioural, or sometimes genetic.

[CaptainKipard]

The problem I have with a phenotypical distinction is that it would make certain breeds of dogs, like bulldogs, a separate species from other dogs while still sharing an overwhelming percentage of DNA with other dogs.

[KerikBalm]

microbiologists use 97% or under similarity results from DNA hybridisation,

No we don't.

But you are right about the definition thing being a mess. For as useful as the interbreeding definitions are, they are completely inadequate for asexual species, or where "***" is not linked to reproduction (as in bacterial conjugation, which may be interspecies anyway).

"Reproductive isolation" is often used instead, which would still allow for two animals to be classified into two separate species, even if it is possible for them to produce fertile offspring (the isolation could be behavioral, or geographical, for instance)

Ring Species make that not so useful either.

In the end, we must accept that classification systems are somewhat arbitrary human constructs. As such, many people will just stop arguing one way or another, and consider the whole argument irrelevant.

Likewise the levels of the old Linnaean taxonomy system are arbitrary. What constitutes a genus is arbitrary (there is much uproar among d. melanogaster scientists, over the proposal to split the genus into two separates genuses - a drosophilia and a sophophora genus, with melanogaster going into sophophora).

Cladistics is nice, but ultimately we just use an arbitary resolution cut off. Really, you'd be following each individual in a population, each individual would be a branch on the cladogram, and you'd have a lot of intertwined/repeatedly merging and separating branches as individuals reproduce sexualy.

In which case clustering and network analysis is more appropriate to at least make objective definitions for species (even if its still arbitrary, its better than arbitrary *and* subjective)

[Klingon Admiral]

It's really kind of a mess.

Biology in a nutshell. It's without doubt the least accurate of the natural sciences.

Back to topic though:

Why has nobody brought up the maybe biggest pronlem with de-extinction of long extinct species yet? Just reviving the animal won't do it. Everey living being is a ecosystem in itself, hosting countless numbers of different bacteria and other miniscule critters which often live in a symbiontic relationship with their host animal. Take for example the gut flora of many animals, which is of critical importance for the digestion of certain nutrients and without which a animal has no chance to survive. And this microroganisms are of course evolving with their host species, and we have absolutely no way to bring them back to life. There goes your premise yet again, Jurassic Park.