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> Shortly after humans arrived, however, Genyornis went extinct. The birds are thought to have been eaten into extinction, with climate change hastening their d

> Shortly after humans arrived, however, Genyornis went extinct. The birds are thought to have been eaten into extinction, with climate change hastening their demise. It’s funny how they (and all the other large mammals) survived for 1.8M years of massive global climate change but the period just after we arrived (like in the Americas) was what “hastened their demise” rather than the humans with clubs they hadn’t had time to evolve to be scared of, eating every last one of them.

justinclift 2y ago
I guess they tasted really, really good? :)
elmomle 2y ago
> The paper suggests that these adaptations might be a sign that the bird was already struggling before the arrival of humans. Changing climate patterns meant that wet areas like Lake Callabonna started getting drier around 60,000 years ago and dried up completely 12,000 years later. > There are indications that the legs of Genyornis were gradually adapting to this drier climate, but the species would have remained under considerable pressure. This environmental stress is thought to be why the birds had higher than expected levels of bone disease at around the same time. In this case it sounds like climate change was in fact a stressor, though I believe you're right--even without climate change this bird would have gone the way of the moa. Perhaps a better phrasing would have been "Already under stress from climate change, they are thought to have been eaten to extinction."
- chrisco255 2y ago
  Disagree with this assessment. There was not large numbers of humans until the end of the glacial period and the advent of pastoralism and agriculture.
  - Jedd 2y ago
    > pastoralism and agriculture? Which landmass / culture / epoch are you trying to describe here?
    - helpfulContrib 2y ago
      [dead]
    - Jedd 2y ago
      @helpfulContrib - I can't reply your message directly. I'm not trying to deny anything. I'm sure there were pockets of what we (modern) might recognise as agriculture, though not pastoralism (for obvious reasons). My question was actually just what it looked like, an earnest question to chrisco255, replying to elmomie, about the context of their statements. GP seemed to be talking global, and so did parent - which would make sense in the context of climate change (a global phenomenon) and also massive human population growth (also mostly global, resulting form settlements / agriculture).
      - chrisco255 2y ago
        Most estimates put the total global human population at less than 1 million prior to the end of the glacial period and the beginning of the Holocene. For most of the globe agriculture was not possible. While canines were probably domesticated in the glacial period, they served as hunting partners primarily. It's actually quite hard to build fencing over large amounts of land area (like sheep and cows require) that is capable of keeping animals in, unless you have metal to cut wood with. The United States had open cattle ranging until barbed wire was invented in the 1870s, since it was too difficult to fence. And open ranging was only possible after horse domestication. We also do not see evidence of grain domestication or any kind of real farming until the start of the Holocene 10K-12K years ago. The climate was not particularly friendly to farming, and without access to metal, farming is orders of magnitude more difficult. The original article is about Australia alone, and 45K years ago, Australia probably had a human population in the low thousands, with it being on the frontier of human expansion at the time. There is no evidence of massive human population at that time or any time before 12K years ago. In fact, there's several population bottlenecks where they think the total number of humans alive globally was around a few thousand. https://pubmed.ncbi.nlm.nih.gov/9650103/ https://pubmed.ncbi.nlm.nih.gov/9650103/ https://pubmed.ncbi.nlm.nih.gov/18922561/ https://pubmed.ncbi.nlm.nih.gov/18922561/
- llm_trw 2y ago
  For one species, sure, for 35 you have to wonder how ideologically driven you have to be to keep blaming the environment. We're at tobacco companies in the 90s level of denialism here.
  - strken 2y ago
    This is an uncharitable interpretation of the facts. The thing about climate change in prehistory is that it drives changes to human life. Archaeologists put glacial maxima on their timelines because it's such an important factor when trying to understanding human migration, the spread of new technologies that do better in drier or wetter climates, the shift to different food sources, and so on. This predates the current climate-aware political landscape. If 90% of a species is killed off by climate change, and if for hundreds of thousands of years that species survived glacial maxima in reservoir populations in areas that are now populated by starving humans who kill the remaining 10%, was it the climate or the humans who wiped out the species? The changing climate killed more, but the humans were the differentiating factor, so which one do you point the finger at? I don't think it's right to call that denialism.
    - llm_trw 2y ago
      [flagged]
      - pipe2devnull 2y ago
        I’m not disagreeing with the premise of what you are saying but did you read the article? At least with this I don’t think anyone was saying it was the British that made it go extinct. The article references a study saying about the native people eating the eggs like 50,000 years ago.
    - N0b8ez 2y ago
      > The changing climate killed more, but the humans were the differentiating factor, so which one do you point the finger at? If we're the differentiating factor, I'd have to blame us. Am I right in understanding that these species were normally being thinned during each glacial maxima, such that it was already a set part of their evolutionary environment? If that's right, then aren't we the ones to blame? Otherwise, is a murderer merely a "contributing cause" to someone's death if the victim happens to be sick at the time of the killing?
defrost 2y ago
There's a lot of divided opinion there in the informed community, not many think that humans soley wiped out the megafauna, a good number question whether they played a significant decisive role in their demise, most think humans killed and ate a few. What is certain is the same change in global conditions that allowed humans to walk to Australia and later filled the moat coincided with the fall off in megafauna. There's correlation, but causation?? The divided opinions: Climate change not to blame for late Quaternary megafauna extinctions in Australia (2016) https://www.nature.com/articles/ncomms10511 https://www.nature.com/articles/ncomms10511 Humans killed most of Australia’s megafauna: study (2017) https://www.australiangeographic.com.au/news/2017/01/humans-killed-most-of-australias-megafauna-study/ https://www.australiangeographic.com.au/news/2017/01/humans-... Did people or climate kill off the megafauna? Actually, it was both (2019) https://theconversation.com/did-people-or-climate-kill-off-the-megafauna-actually-it-was-both-127803 https://theconversation.com/did-people-or-climate-kill-off-t... Humans coexisted with three-tonne marsupials and lizards as long as cars (2020) https://theconversation.com/humans-coexisted-with-three-tonne-marsupials-and-lizards-as-long-as-cars-in-ancient-australia-138534 https://theconversation.com/humans-coexisted-with-three-tonn... It turns out humans coexisted with the megafauna over about 80% of south-eastern Sahul for up to 15,000 years, depending on the region in question. In other regions such as Tasmania, there was no such coexistence. This rules out humans as a likely driver of megafauna extinction in those areas.
- sethammons 2y ago
  You seem certain on something that is not certain. People likely traveled over water. Ancient people were very impressive. From https://digital-classroom.nma.gov.au/learning-modules/ancient-australia-defining-moments/22-big-idea-1-scientists-believe-first-australians-came-somewhere-else#:~:text=The%20first%20people%20probably%20came,been%20a%20remarkable%20maritime%20achievement https://digital-classroom.nma.gov.au/learning-modules/ancien.... > The first people probably came to Australia from around the area that is now Timor. To get to Australia, they must have made a canoe voyage of about 90 to 150 kilometres of open water, which would have been a remarkable maritime achievement
  - defrost 2y ago
derefr 2y ago
The climate change gave them fewer places to hide from the humans with clubs.
chrisco255 2y ago
> humans with clubs they hadn’t had time to evolve to be scared of This is not a thing. Species don't require generations to learn to be afraid of other species that hunt them. Species have encountered new species since the beginning of time. If it took 1000 generations to learn such a thing, nothing would have ever made it. It's not as if there's a shortage of dangerous predators in Australia, even to this day. Just because an article hand waves an explanation doesn't make it so.
- acyou 2y ago
  It takes surprisingly few generations to evolve traits. If there is a distribution of skittishness and a high pass filter takes away everything under a given limit, you'll get rapid evolution. As another example, urban populations of animals have evolved to tolerate noise in the span of very few generations. Giant flightless goose- very tasty!
- throwup238 2y ago
  > due to the lack of natural predators, the wildlife in the Galápagos is known for being extremely tame without instinctual fear. https://en.m.wikipedia.org/wiki/Gal%C3%A1pagos_wildlife https://en.m.wikipedia.org/wiki/Gal%C3%A1pagos_wildlife We have actual evidence that it is a developed instinct. If you’ve ever been to the Galapagos islands, it’s extremely obvious. The sea lions and pelicans casually walk up to the counter at the fish market as if they’re just regulars shopping.
HyulianGrader 2y ago
[flagged]
noelwelsh 2y ago
It's worth noting there is also evidence that the Australian aborigines changed the climate, making Australia drier, with their hunting practice of burning forest: https://theconversation.com/how-aboriginal-burning-changed-australias-climate-4454 https://theconversation.com/how-aboriginal-burning-changed-a...
- defrost 2y ago
  Strictly speaking there's no evidence just suggestion and opinion. Associate Professor Karl-Heinz Wyrwoll has littered his article with qualifiers: * During the last few decades, human-induced climate change has been a pervasive theme in the scientific literature. * Ruddiman’s research, while not without its critics, suggests that these resultant climatic changes ... * This is the idea that early agriculturalists caused an anomalous reversal ... * He showed that vegetation clearing, overgrazing and burning may have had an impact ... * Tom Lyons’ “bunny fence” experiments have drawn attention to likely climate impacts and feedbacks ... etc. I'm neither agreeing nor disagreeing with the notions put forward, just highlighting that the article is not as you paraphrased it.
  - chownie 2y ago
    No, that is what constitutes the word evidence, I think you've mistaken the meaning of proof for the meaning of evidence. There is evidence that aborigines affected the climate, but there is not proof.
- lmpdev 2y ago
  I’m not aware of it changing our climate but it’s an essential process even today We back burn areas most likely to cause uncontrollable bushfires in the future Most of the continent requires fire, with the notable exception of Tassie and some rainforests scattered throughout the mainland
  - Jedd 2y ago
    I think the suggestion is that the flora ~80,000 ya did not need fire so much as it does today, and that the change in fire requirement was a result of broad-scale, regular, frequent, intentionally lit fires. Adaptation and species selection has resulted in what we have now -- as distinct from finding ourselves in a land that happens to need regular burning. Contrast us with comparable latitudes (15-35 from the equator) on other landmasses.
hyperthesis 2y ago
The climate change created land bridges. https://xkcd.com/552 https://xkcd.com/552
Sparkyte 2y ago
Must be why Canadian geese are so aggressive. Jokes aside bet they tasted good.

justinclift 2y ago

I guess they tasted really, really good? :)

elmomle 2y ago

> The paper suggests that these adaptations might be a sign that the bird was already struggling before the arrival of humans. Changing climate patterns meant that wet areas like Lake Callabonna started getting drier around 60,000 years ago and dried up completely 12,000 years later. > There are indications that the legs of Genyornis were gradually adapting to this drier climate, but the species would have remained under considerable pressure. This environmental stress is thought to be why the birds had higher than expected levels of bone disease at around the same time. In this case it sounds like climate change was in fact a stressor, though I believe you're right--even without climate change this bird would have gone the way of the moa. Perhaps a better phrasing would have been "Already under stress from climate change, they are thought to have been eaten to extinction."

chrisco255 2y ago
Disagree with this assessment. There was not large numbers of humans until the end of the glacial period and the advent of pastoralism and agriculture.
- Jedd 2y ago
  > pastoralism and agriculture? Which landmass / culture / epoch are you trying to describe here?
  - helpfulContrib 2y ago
    [dead]
  - Jedd 2y ago
    @helpfulContrib - I can't reply your message directly. I'm not trying to deny anything. I'm sure there were pockets of what we (modern) might recognise as agriculture, though not pastoralism (for obvious reasons). My question was actually just what it looked like, an earnest question to chrisco255, replying to elmomie, about the context of their statements. GP seemed to be talking global, and so did parent - which would make sense in the context of climate change (a global phenomenon) and also massive human population growth (also mostly global, resulting form settlements / agriculture).
    - chrisco255 2y ago
      Most estimates put the total global human population at less than 1 million prior to the end of the glacial period and the beginning of the Holocene. For most of the globe agriculture was not possible. While canines were probably domesticated in the glacial period, they served as hunting partners primarily. It's actually quite hard to build fencing over large amounts of land area (like sheep and cows require) that is capable of keeping animals in, unless you have metal to cut wood with. The United States had open cattle ranging until barbed wire was invented in the 1870s, since it was too difficult to fence. And open ranging was only possible after horse domestication. We also do not see evidence of grain domestication or any kind of real farming until the start of the Holocene 10K-12K years ago. The climate was not particularly friendly to farming, and without access to metal, farming is orders of magnitude more difficult. The original article is about Australia alone, and 45K years ago, Australia probably had a human population in the low thousands, with it being on the frontier of human expansion at the time. There is no evidence of massive human population at that time or any time before 12K years ago. In fact, there's several population bottlenecks where they think the total number of humans alive globally was around a few thousand. https://pubmed.ncbi.nlm.nih.gov/9650103/ https://pubmed.ncbi.nlm.nih.gov/9650103/ https://pubmed.ncbi.nlm.nih.gov/18922561/ https://pubmed.ncbi.nlm.nih.gov/18922561/
llm_trw 2y ago
For one species, sure, for 35 you have to wonder how ideologically driven you have to be to keep blaming the environment. We're at tobacco companies in the 90s level of denialism here.
- strken 2y ago
  This is an uncharitable interpretation of the facts. The thing about climate change in prehistory is that it drives changes to human life. Archaeologists put glacial maxima on their timelines because it's such an important factor when trying to understanding human migration, the spread of new technologies that do better in drier or wetter climates, the shift to different food sources, and so on. This predates the current climate-aware political landscape. If 90% of a species is killed off by climate change, and if for hundreds of thousands of years that species survived glacial maxima in reservoir populations in areas that are now populated by starving humans who kill the remaining 10%, was it the climate or the humans who wiped out the species? The changing climate killed more, but the humans were the differentiating factor, so which one do you point the finger at? I don't think it's right to call that denialism.
  - llm_trw 2y ago
    [flagged]
    - pipe2devnull 2y ago
      I’m not disagreeing with the premise of what you are saying but did you read the article? At least with this I don’t think anyone was saying it was the British that made it go extinct. The article references a study saying about the native people eating the eggs like 50,000 years ago.
  - N0b8ez 2y ago
    > The changing climate killed more, but the humans were the differentiating factor, so which one do you point the finger at? If we're the differentiating factor, I'd have to blame us. Am I right in understanding that these species were normally being thinned during each glacial maxima, such that it was already a set part of their evolutionary environment? If that's right, then aren't we the ones to blame? Otherwise, is a murderer merely a "contributing cause" to someone's death if the victim happens to be sick at the time of the killing?

defrost 2y ago

There's a lot of divided opinion there in the informed community, not many think that humans soley wiped out the megafauna, a good number question whether they played a significant decisive role in their demise, most think humans killed and ate a few. What is certain is the same change in global conditions that allowed humans to walk to Australia and later filled the moat coincided with the fall off in megafauna. There's correlation, but causation?? The divided opinions: Climate change not to blame for late Quaternary megafauna extinctions in Australia (2016) https://www.nature.com/articles/ncomms10511 https://www.nature.com/articles/ncomms10511 Humans killed most of Australia’s megafauna: study (2017) https://www.australiangeographic.com.au/news/2017/01/humans-killed-most-of-australias-megafauna-study/ https://www.australiangeographic.com.au/news/2017/01/humans-... Did people or climate kill off the megafauna? Actually, it was both (2019) https://theconversation.com/did-people-or-climate-kill-off-the-megafauna-actually-it-was-both-127803 https://theconversation.com/did-people-or-climate-kill-off-t... Humans coexisted with three-tonne marsupials and lizards as long as cars (2020) https://theconversation.com/humans-coexisted-with-three-tonne-marsupials-and-lizards-as-long-as-cars-in-ancient-australia-138534 https://theconversation.com/humans-coexisted-with-three-tonn... It turns out humans coexisted with the megafauna over about 80% of south-eastern Sahul for up to 15,000 years, depending on the region in question. In other regions such as Tasmania, there was no such coexistence. This rules out humans as a likely driver of megafauna extinction in those areas.

sethammons 2y ago
You seem certain on something that is not certain. People likely traveled over water. Ancient people were very impressive. From https://digital-classroom.nma.gov.au/learning-modules/ancient-australia-defining-moments/22-big-idea-1-scientists-believe-first-australians-came-somewhere-else#:~:text=The%20first%20people%20probably%20came,been%20a%20remarkable%20maritime%20achievement https://digital-classroom.nma.gov.au/learning-modules/ancien.... > The first people probably came to Australia from around the area that is now Timor. To get to Australia, they must have made a canoe voyage of about 90 to 150 kilometres of open water, which would have been a remarkable maritime achievement
- defrost 2y ago

derefr 2y ago

The climate change gave them fewer places to hide from the humans with clubs.

chrisco255 2y ago

> humans with clubs they hadn’t had time to evolve to be scared of This is not a thing. Species don't require generations to learn to be afraid of other species that hunt them. Species have encountered new species since the beginning of time. If it took 1000 generations to learn such a thing, nothing would have ever made it. It's not as if there's a shortage of dangerous predators in Australia, even to this day. Just because an article hand waves an explanation doesn't make it so.

acyou 2y ago
It takes surprisingly few generations to evolve traits. If there is a distribution of skittishness and a high pass filter takes away everything under a given limit, you'll get rapid evolution. As another example, urban populations of animals have evolved to tolerate noise in the span of very few generations. Giant flightless goose- very tasty!
throwup238 2y ago
> due to the lack of natural predators, the wildlife in the Galápagos is known for being extremely tame without instinctual fear. https://en.m.wikipedia.org/wiki/Gal%C3%A1pagos_wildlife https://en.m.wikipedia.org/wiki/Gal%C3%A1pagos_wildlife We have actual evidence that it is a developed instinct. If you’ve ever been to the Galapagos islands, it’s extremely obvious. The sea lions and pelicans casually walk up to the counter at the fish market as if they’re just regulars shopping.

HyulianGrader 2y ago

[flagged]

noelwelsh 2y ago

It's worth noting there is also evidence that the Australian aborigines changed the climate, making Australia drier, with their hunting practice of burning forest: https://theconversation.com/how-aboriginal-burning-changed-australias-climate-4454 https://theconversation.com/how-aboriginal-burning-changed-a...

defrost 2y ago
Strictly speaking there's no evidence just suggestion and opinion. Associate Professor Karl-Heinz Wyrwoll has littered his article with qualifiers: * During the last few decades, human-induced climate change has been a pervasive theme in the scientific literature. * Ruddiman’s research, while not without its critics, suggests that these resultant climatic changes ... * This is the idea that early agriculturalists caused an anomalous reversal ... * He showed that vegetation clearing, overgrazing and burning may have had an impact ... * Tom Lyons’ “bunny fence” experiments have drawn attention to likely climate impacts and feedbacks ... etc. I'm neither agreeing nor disagreeing with the notions put forward, just highlighting that the article is not as you paraphrased it.
- chownie 2y ago
  No, that is what constitutes the word evidence, I think you've mistaken the meaning of proof for the meaning of evidence. There is evidence that aborigines affected the climate, but there is not proof.
lmpdev 2y ago
I’m not aware of it changing our climate but it’s an essential process even today We back burn areas most likely to cause uncontrollable bushfires in the future Most of the continent requires fire, with the notable exception of Tassie and some rainforests scattered throughout the mainland
- Jedd 2y ago
  I think the suggestion is that the flora ~80,000 ya did not need fire so much as it does today, and that the change in fire requirement was a result of broad-scale, regular, frequent, intentionally lit fires. Adaptation and species selection has resulted in what we have now -- as distinct from finding ourselves in a land that happens to need regular burning. Contrast us with comparable latitudes (15-35 from the equator) on other landmasses.

hyperthesis 2y ago

The climate change created land bridges. https://xkcd.com/552 https://xkcd.com/552

Sparkyte 2y ago

Must be why Canadian geese are so aggressive. Jokes aside bet they tasted good.