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If I understand this correctly, asexual reproduction in plants is called apomixis[0] and the dandelions and blackberries have been doing it for millions of year

If I understand this correctly, asexual reproduction in plants is called apomixis[0] and the dandelions and blackberries have been doing it for millions of years. In animals it is called parthenogenesis and happens in lizards, snakes, birds and sharks[1]. All of them have been around quite some time on earth, also. What helped these species to be so resilient to a devastating infection when other animals that reproduce sexually (Central American frogs, North American bats) are being wiped away so badly by fungal infections? [0] https://en.wikipedia.org/wiki/Apomixis https://en.wikipedia.org/wiki/Apomixis [1] https://en.wikipedia.org/wiki/Parthenogenesis#Natural_occurrence https://en.wikipedia.org/wiki/Parthenogenesis#Natural_occurr...

justinjlynn 9y ago
Asexual reproduction gives an individual (in the genetic sense) more time to reproduce while also acting as something of a checksum on the genome as a whole. Survival during disease outbreaks would certainly be increased if one didn't need to balance infection versus dying of old age against somewhat more genetically advantageous sexual reproduction. It's an interesting delay tactic.
icegreentea2 9y ago
It could literally just be time and luck. We started mass production (cloning) of cavendish bananas around the the 1900s, and REALLY started mass production (cloning) in the 1950s, we only started seeing strains of banana blight effect it in the last few decades. Obviously there are all sorts of differences between these cases, but it's probably worth thinking about a bit. Oh, also it looks like most animals capable of parthenogenesis can also under go sexual reproduction, helping them hedge against certain types of threats. Also remember that we're looking at animal population on human generation timescales. One might say that a species with a population of millions being wiped out to a population of thousands (that are fungal resistant) over a time scale of 60 years as a 'disaster'. It in our life time it probably is, cause our activities would probably completely fuck over whatever is left. But in the absense of our activity, those thousands or so could still form a viable population and if they still have a good ecological niche to occupy, could easily within a few hundred/thousand years regain their original population. And we'd be all completely blind to that, cause that's not how we tend to think.
- IncRnd 9y ago
  > we only started seeing strains of banana blight effect it in the last few decades. ... it's probably worth thinking about a bit. It was likely an oversight to not mention why we started to clone the Cavendish. Panama disease devastated the also cloned Gros Michel cultivar over 60 years ago. That's why, today, we eat a different banana than those who came before us.
thaumasiotes 9y ago
> All of them have been around quite some time on earth, also. Asexual species have been around for "quite some time" by comparison to, say, all of recorded history. They tend to be very recent on a geological timescale. http://www.razib.com/wordpress/?p=101136 http://www.razib.com/wordpress/?p=101136
- jobigoud 9y ago
  > Asexual species have been around for "quite some time" by comparison to, say, all of recorded history. They tend to be very recent on a geological timescale. Asexual reproduction was there first and predates sexual reproduction by several billion years. Some species then evolved back asexual reproduction, like this marbled crayfish.
  - masklinn 9y ago
    Asexual reproduction yes, but GP's point is that asexual species seem much younger, seem to generally speaking not "last" on long timescales. Which would make sense, if an individual has great fitness they can "boom" extremely rapidly, but then any change in condition or emergence of specialised predator or disease will take down the entire population just as quickly because it has very low variability and flexibility.
    - jobigoud 9y ago
      Ah, thanks for the clarification. But then all species, asexual or not, are young with regards to geological times. I think the order of magnitude for longest species lifespan is about 10 million years. Is there really a correlation between species lifespan and method of reproduction?
      - Scarblac 9y ago
        This crayfish evolved 25 years ago. The article cites another study on asexual flea species, where the mutation was 1250 years old. That's two examples and both very far away from 10 million years.
vanderZwan 9y ago
Low genetic diversity can have unexpected benefits; within Argentine ants it has given rise to a global supercolony, because the pheromones of different hives have become indistinguishable. https://en.wikipedia.org/wiki/Ant_colony#Supercolonies https://en.wikipedia.org/wiki/Ant_colony#Supercolonies
- MaxBarraclough 9y ago
  Neat. Ants really are one of the most interesting species. (Or, if not species, whatever the appropriate taxonomical term is.)
ioddly 9y ago
IIRC some of those animals that can reproduce asexually don't necessarily do it exclusively (sharks).
baybal2 9y ago
>What helped these species to be so resilient to a devastating infection when other animals that reproduce sexually (Central American frogs, North American bats) are being wiped away so badly by fungal infections? At least some plants have genes that randomise genetic code if I recall my high school biology well. I also read that polyploid plants have something to randomly shuffle chromosome sets. Quite alike a stack randomisation it is
Brockenstein 9y ago
>What helped these species to be so resilient to a devastating infection when other animals Well for starters asexual reproduction is an option for them, not the sole means of reproduction. Secondly, diseases and catastrophes strike all sorts of critters and sometimes no amount of genetic variation will save them. For example you mention snakes and their resilience: http://www.bbc.com/news/science-environment-42428528 http://www.bbc.com/news/science-environment-42428528 Thirdly, snakes, lizards, sharks, make up a huge number of species and genetic variability with global distribution. That provides some protection. And for most of history global pandemics were probably less common or were slow enough that it didn't happen at once everywhere. And if enough individuals survive for the species to recover, then that's that. Fourth, sexual reproduction isn't a guarantee of immunity to disease, it's a survival strategy to help increase the odds of surviving as a species or having individuals with immunity because of all the possible combinations of genes being tried. For example, AIDS (without treatment) is lethal for most of the human population. But there are a few Scandinavian groups that have partial or full immunity, something like less than 1% of the total human population. That's what sexual reproduction gets us as a species.

justinjlynn 9y ago

Asexual reproduction gives an individual (in the genetic sense) more time to reproduce while also acting as something of a checksum on the genome as a whole. Survival during disease outbreaks would certainly be increased if one didn't need to balance infection versus dying of old age against somewhat more genetically advantageous sexual reproduction. It's an interesting delay tactic.

icegreentea2 9y ago

It could literally just be time and luck. We started mass production (cloning) of cavendish bananas around the the 1900s, and REALLY started mass production (cloning) in the 1950s, we only started seeing strains of banana blight effect it in the last few decades. Obviously there are all sorts of differences between these cases, but it's probably worth thinking about a bit. Oh, also it looks like most animals capable of parthenogenesis can also under go sexual reproduction, helping them hedge against certain types of threats. Also remember that we're looking at animal population on human generation timescales. One might say that a species with a population of millions being wiped out to a population of thousands (that are fungal resistant) over a time scale of 60 years as a 'disaster'. It in our life time it probably is, cause our activities would probably completely fuck over whatever is left. But in the absense of our activity, those thousands or so could still form a viable population and if they still have a good ecological niche to occupy, could easily within a few hundred/thousand years regain their original population. And we'd be all completely blind to that, cause that's not how we tend to think.

IncRnd 9y ago
> we only started seeing strains of banana blight effect it in the last few decades. ... it's probably worth thinking about a bit. It was likely an oversight to not mention why we started to clone the Cavendish. Panama disease devastated the also cloned Gros Michel cultivar over 60 years ago. That's why, today, we eat a different banana than those who came before us.

thaumasiotes 9y ago

> All of them have been around quite some time on earth, also. Asexual species have been around for "quite some time" by comparison to, say, all of recorded history. They tend to be very recent on a geological timescale. http://www.razib.com/wordpress/?p=101136 http://www.razib.com/wordpress/?p=101136

jobigoud 9y ago
> Asexual species have been around for "quite some time" by comparison to, say, all of recorded history. They tend to be very recent on a geological timescale. Asexual reproduction was there first and predates sexual reproduction by several billion years. Some species then evolved back asexual reproduction, like this marbled crayfish.
- masklinn 9y ago
  Asexual reproduction yes, but GP's point is that asexual species seem much younger, seem to generally speaking not "last" on long timescales. Which would make sense, if an individual has great fitness they can "boom" extremely rapidly, but then any change in condition or emergence of specialised predator or disease will take down the entire population just as quickly because it has very low variability and flexibility.
  - jobigoud 9y ago
    Ah, thanks for the clarification. But then all species, asexual or not, are young with regards to geological times. I think the order of magnitude for longest species lifespan is about 10 million years. Is there really a correlation between species lifespan and method of reproduction?
    - Scarblac 9y ago
      This crayfish evolved 25 years ago. The article cites another study on asexual flea species, where the mutation was 1250 years old. That's two examples and both very far away from 10 million years.

vanderZwan 9y ago

Low genetic diversity can have unexpected benefits; within Argentine ants it has given rise to a global supercolony, because the pheromones of different hives have become indistinguishable. https://en.wikipedia.org/wiki/Ant_colony#Supercolonies https://en.wikipedia.org/wiki/Ant_colony#Supercolonies

MaxBarraclough 9y ago
Neat. Ants really are one of the most interesting species. (Or, if not species, whatever the appropriate taxonomical term is.)

ioddly 9y ago

IIRC some of those animals that can reproduce asexually don't necessarily do it exclusively (sharks).

baybal2 9y ago

>What helped these species to be so resilient to a devastating infection when other animals that reproduce sexually (Central American frogs, North American bats) are being wiped away so badly by fungal infections? At least some plants have genes that randomise genetic code if I recall my high school biology well. I also read that polyploid plants have something to randomly shuffle chromosome sets. Quite alike a stack randomisation it is

Brockenstein 9y ago

>What helped these species to be so resilient to a devastating infection when other animals Well for starters asexual reproduction is an option for them, not the sole means of reproduction. Secondly, diseases and catastrophes strike all sorts of critters and sometimes no amount of genetic variation will save them. For example you mention snakes and their resilience: http://www.bbc.com/news/science-environment-42428528 http://www.bbc.com/news/science-environment-42428528 Thirdly, snakes, lizards, sharks, make up a huge number of species and genetic variability with global distribution. That provides some protection. And for most of history global pandemics were probably less common or were slow enough that it didn't happen at once everywhere. And if enough individuals survive for the species to recover, then that's that. Fourth, sexual reproduction isn't a guarantee of immunity to disease, it's a survival strategy to help increase the odds of surviving as a species or having individuals with immunity because of all the possible combinations of genes being tried. For example, AIDS (without treatment) is lethal for most of the human population. But there are a few Scandinavian groups that have partial or full immunity, something like less than 1% of the total human population. That's what sexual reproduction gets us as a species.