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Unsurprising. Amazonia itself has been called a "manufactured landscape". 10% of its soil is man-made terra preta. The distribution of many important plants li

by culi 3y ago

Unsurprising. Amazonia itself has been called a "manufactured landscape". 10% of its soil is man-made terra preta. The distribution of many important plants like brazil nuts simply can't be explained without accounting for distributions of different peoples. 84% of all arboreal plants in the Amazon are known to be useful to humans[0] (edible, medicinal, etc). More likely than the Amazon magically just being a more special place is that the possibly 8-10 million[1] native inhabitants (pre colonial) selected and planted them. California's increasingly dangerous wildfires are largely due to the fact that it banned traditional cultural burning (before California itself was even legally a state even!). These highly controlled "cool fires" got rid of fuel that now builds up and causes the devastating wildfires of today. They also cleaned rivers (due to the charcoal that was produced) and obviously helped acorns produce much larger bounties. These burns have been going on for at least 10k years so much of the flora is highly adapted. Some sage species can't even germinate without the presence of ashes. Despite this reliance on fire, they also simply can't handle the powerful wildfires of today Many European colonists who came to Australia often described it as looking like a giant well-managed park. It turns out much of it really was. Similar to native Californians, complex fire regimes were often used for landscape management. But colonist writings also describe fields of pulled up grass that spanned out for many miles. It turned out aboriginals used hayricks to ripen seeds in the grass. They often grew native grains and would use it to make flour and bread.[2] If you'd like to read more, there's a great book on this topic called Black Emu: Dark Seed. Everywhere you look humans have had to very tightly integrate into their ecosystems. This is why "conservation" practices are often criticized by indigenous activists for banning indigenous people from their lands. Our ecosystems are as dependent on us as we are on them and there's a desperate need for a more expansive definition of conservation that includes active interdependence with nature rather than trying to box away nature to preserve some idea of a "pristine landscape" that never actually existed [0] https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0257875 https://journals.plos.org/plosone/article?id=10.1371/journal... [1] https://sci-hub.se/https://www.jstor.org/stable/24395921 https://sci-hub.se/https://www.jstor.org/stable/24395921 [2] https://en.wikipedia.org/wiki/Bush_bread https://en.wikipedia.org/wiki/Bush_bread

Kaijo 3y ago
"The Amazon" and some of the other habitats you mention, all very different in their ecologies (and especially their relationship to fire), have had very complex histories, but their co-history with humans must be seen as a recent history in relation to the evolutionary history of their core community structures and the tens of millions of species of which they are composed. Of course once we first arrived in South America, only about 20,000 years ago, we had quite profound impacts on the Amazon's species composition and distribution, but... that's a mere 20,000 years ago, and essentially all the species we see in today's Amazon were already there, just configured differently. Before that, there was certainly a highly biodiverse and to all intents modern Amazon pre-dating humans by millions of years, one in which, if we could go back, we could still find regions plainly characteristic of every major present-day Amazonian ecotype, minus humans. This applies even more so to the much more ancient central African and southeast Asian rainforests in which there are also some areas with no clear record of inhabitation. I have done fieldwork in such areas and am fine with the characterization that they present a "more pristine" state of ecological affairs, as would most biologists focusing on tropical forest ecology rather than anthropology. To claim all these habitats are intrinsically human-oriented ecosystems that have always been as dependent on us as we on them is myopic. That's a view of how things have to be going forwards. But to them we're a recent development.
- culi 3y ago
  Thanks for the comment. Would love to hear more about what kind of fieldwork you've done > Of course once we first arrived in South America, only about 20,000 years ago, we had quite profound impacts on the Amazon's species composition and distribution, but... that's a mere 20,000 years ago Consider the fact that only just 12,000 years ago the Amazon transitioned from mostly grasslands to the full-fledged continent-wide jungle it is today. Or that the last African humid period ended just 6,000 years ago during which the Sahara was covered with wetlands, grasses, trees, etc. A LOT can change in just a few thousand years > Before that, there was certainly a highly biodiverse and to all intents modern Amazon pre-dating humans by millions of years Sure, if we're talking on the scale of millions of years we can include a jungled Arctic which also ended 50 millions ago (around the same age as the Amazon). I did not intend to argue humans were necessary to biodiversity or even to the Amazon's development. Rather just that they clearly left a major impact. From that first paper I linked: > We found that half of the arboreal species (2,253) are useful to humans, which represents 84% of the estimated individuals in Amazonian forests. Useful species have mean populations sizes six times larger than non-useful species, and their abundance is related with the probability of usefulness. Incipiently domesticated species are the most abundant Of course naturally people will often use the most abundant species (the paper addresses that as well), but it's hard to deny that the millions of native Homo sapiens acted as a keystone species. The recent advances in Lidar technologies especially have revealed an Amazonian landscape and soil distribution that's been deeply shaped by human inhabitation. > if we could go back, we could still find regions plainly characteristic of every major present-day Amazonian ecotype, minus humans This seems like an incredibly hard claim to back up but I would be absolutely delighted to read through any papers or books on the topic if you have them on hand > This applies even more so to the much more ancient central African and southeast Asian rainforests in which there are also some areas with no clear record of inhabitation Yes, apologies if I seemed to imply that every corner of earth was shaped by humans. This is certainly not true. I did not mention the landscapes you brought up, but I stand by the claim that there is plenty of evidence that the 3 case studies I brought up are heavily shaped by human culture despite often being portrayed as "untouched" environments > But to them we're a recent development. I completely agree with this statement but go back to my first point (and I even made the point without bringing up climate change!)

by culi 3y ago

Kaijo 3y ago

"The Amazon" and some of the other habitats you mention, all very different in their ecologies (and especially their relationship to fire), have had very complex histories, but their co-history with humans must be seen as a recent history in relation to the evolutionary history of their core community structures and the tens of millions of species of which they are composed. Of course once we first arrived in South America, only about 20,000 years ago, we had quite profound impacts on the Amazon's species composition and distribution, but... that's a mere 20,000 years ago, and essentially all the species we see in today's Amazon were already there, just configured differently. Before that, there was certainly a highly biodiverse and to all intents modern Amazon pre-dating humans by millions of years, one in which, if we could go back, we could still find regions plainly characteristic of every major present-day Amazonian ecotype, minus humans. This applies even more so to the much more ancient central African and southeast Asian rainforests in which there are also some areas with no clear record of inhabitation. I have done fieldwork in such areas and am fine with the characterization that they present a "more pristine" state of ecological affairs, as would most biologists focusing on tropical forest ecology rather than anthropology. To claim all these habitats are intrinsically human-oriented ecosystems that have always been as dependent on us as we on them is myopic. That's a view of how things have to be going forwards. But to them we're a recent development.

culi 3y ago
Thanks for the comment. Would love to hear more about what kind of fieldwork you've done > Of course once we first arrived in South America, only about 20,000 years ago, we had quite profound impacts on the Amazon's species composition and distribution, but... that's a mere 20,000 years ago Consider the fact that only just 12,000 years ago the Amazon transitioned from mostly grasslands to the full-fledged continent-wide jungle it is today. Or that the last African humid period ended just 6,000 years ago during which the Sahara was covered with wetlands, grasses, trees, etc. A LOT can change in just a few thousand years > Before that, there was certainly a highly biodiverse and to all intents modern Amazon pre-dating humans by millions of years Sure, if we're talking on the scale of millions of years we can include a jungled Arctic which also ended 50 millions ago (around the same age as the Amazon). I did not intend to argue humans were necessary to biodiversity or even to the Amazon's development. Rather just that they clearly left a major impact. From that first paper I linked: > We found that half of the arboreal species (2,253) are useful to humans, which represents 84% of the estimated individuals in Amazonian forests. Useful species have mean populations sizes six times larger than non-useful species, and their abundance is related with the probability of usefulness. Incipiently domesticated species are the most abundant Of course naturally people will often use the most abundant species (the paper addresses that as well), but it's hard to deny that the millions of native Homo sapiens acted as a keystone species. The recent advances in Lidar technologies especially have revealed an Amazonian landscape and soil distribution that's been deeply shaped by human inhabitation. > if we could go back, we could still find regions plainly characteristic of every major present-day Amazonian ecotype, minus humans This seems like an incredibly hard claim to back up but I would be absolutely delighted to read through any papers or books on the topic if you have them on hand > This applies even more so to the much more ancient central African and southeast Asian rainforests in which there are also some areas with no clear record of inhabitation Yes, apologies if I seemed to imply that every corner of earth was shaped by humans. This is certainly not true. I did not mention the landscapes you brought up, but I stand by the claim that there is plenty of evidence that the 3 case studies I brought up are heavily shaped by human culture despite often being portrayed as "untouched" environments > But to them we're a recent development. I completely agree with this statement but go back to my first point (and I even made the point without bringing up climate change!)