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> 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 t

> 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/
      - Jedd 2y ago
        This is good - in that it aligns with my understanding (though my knowledge was not that detailed on timeline, context, and figures - thank you for those). I know living, brush, or ha-ha type fences would have been possible - but agree all of those were easier with some metal utensils.
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?

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/
    - Jedd 2y ago
      This is good - in that it aligns with my understanding (though my knowledge was not that detailed on timeline, context, and figures - thank you for those). I know living, brush, or ha-ha type fences would have been possible - but agree all of those were easier with some metal utensils.

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?