I'm sorry that I didn't get far yet. Here is the first bunch of points:
It involved changes in Earth's orbit around the Sun, changes in vegetation and dust in the Sahara that altered the African monsoon, the disappearance of much of the Sahara desert which was replaced by grassy vegetation, trees and lakes and the settlement of the former desert by various animals and humans, who survived as hunter-gatherers. – You do not differentiate between causes and effects, why? I would have expected that both are treated separately.
There is kind of a sorting with the cause being first and the effects second. First part is the ultimate cause, second part the feedback effects, third the actual changes and fourth their ramifications.
Jo-Jo Eumerus (
talk,
contributions)
20:56, 16 March 2019 (UTC)reply
Well, I do think that the "interesting" bits needs to stay in, as otherwise a reader unfamiliar with the topic has no idea that there is more to this than a technical article on a climate anomaly thousands of years ago. That necessarily restricts how much of it can be rewritten. Part of the point of a lead section is to hook a reader in to the article.
Jo-Jo Eumerus (
talk,
contributions)
07:17, 25 March 2019 (UTC)reply
I did not mean to remove something, I merely see a prose issue. What about "It was caused by changes in Earth's orbit around the Sun, and involved changes in vegetation …"? --
Jens Lallensack (
talk)
02:58, 25 April 2019 (UTC)reply
It has had profound effects on present-day Africa – as only culture stuff is listed, maybe specify with "present-day African culture"? As Ancient Egypt and the Golden Age myths impacted not only Africa, maybe you can even skip the "present-day Africa"?
My concern with "present-day African culture" is that it's a bit too specific IMO, in terms of timespan. I think that Ancient Egypt should still be considered "Africa". As for the Golden Age myths ... I dunno how to formulate this.
Jo-Jo Eumerus (
talk,
contributions)
20:56, 16 March 2019 (UTC)reply
and had extensive dune fields, many lakes and rivers such – think you need a ";" here instead of the ",". With the latter, it reads like a listing, which misleads the reader.
The African humid period commenced about 14,600–14,500 years ago at the end of Heinrich event 1 and concomitant to the Bølling-Allerød warming, rivers and lakes such as Lake Chad formed or expanded – not especially good with English grammar, but shouldn't this sentence start with "As the African humid period …", or alternatively "with rivers and lakes"?
but the end of the African humid period came about 6,000–5,000 years ago during the Piora Oscillation cold period when the Sahara occupied its present position. – I would start a new sentence here.
which shifted the season during which Earth is closest to the Sun towards Northern Hemisphere summer during the early Holocene – a bit concoluted, lot of stuff put togehter here, not so easy to read. Why not moving the "during the early Holocene" to the sentence "The African humid period commenced …"? Would be more helpful there.
This was not enough to make the Sahara disappear – Suggest "This alone was not enough" for clarity. Otherwise one would assume that it means that the Sahara did not disappear completely.
The terms "Léopoldvillien"[19] and Ogolien [fr] has been applied to the dry period in the last glacial maximum. – These terms are not mentioned again, so I wonder why they are relevant here? Reducing complexity would make it easier for readers.
In addition to drought, glaciers were active in the Bale and Semien Mountains of Ethiopia during the last glacial maximum – I'm confused about the "in addition". To what do drought + glaciers add up? Hostility? What does it want to tell us?
Due to the phenomenon called precession – this is wordy but does not explain anything; I also would not call it a "phenomenon", as it is more of a condition?
This effect was strengthened by the increased summer insolation thus leading to a stronger monsoon that also reached farther north. – This, and the whole paragraph, is basically a repetition of what was already said. Suggest to merge it with the preceding paragraph.
Contrarily, northward transport of moisture during autumn and spring directed by throughs close to Northern Africa has also been proposed to explain the increased precipitation and its underestimation by climate models. – I don't get this
A reduction in open grasslands caused by the African humid period may explain a population bottleneck in cheetahs at the start of the humid period – So they did not move northwards? I thought there was a lot of grass land during the period?
This is going to be tough. This source believes that there may have been less grassland during the AHP. Other sources say it expanded. Seems like at first it may have shrunk; the source does not specify but I made a small change.
Jo-Jo Eumerus (
talk,
contributions)
07:17, 25 March 2019 (UTC)reply
both in Egypt and both feature archeological sites – "featuring"?
The African humid period ended about 6,000-5,000 years ago around 5,500 years before present and after a vegetation decline sand claimed the Sahara which became barren, accompanied by increases in dust export from the now-desert and from dried up lakes. – Long, complicated sentence that is hard to read.
Increased autocorrelation – Again; translate into comprehensible language?
That's a tough one. Even I had to look up "autocorrelation" and it's apparently not something that's easily "translated" as each definition I've seen is just as technically worded; I've stripped it out for the time being.
Jo-Jo Eumerus (
talk,
contributions)
06:22, 25 April 2019 (UTC)reply
calibrated years ago – can this be explained at first mention?
If you wish to submit this to FAC in the future, I would seriously shorten it beforehand. It became too long for a single article. That is ok for becoming GA. --
Jens Lallensack (
talk)
02:58, 25 April 2019 (UTC)reply
@
Jens Lallensack: Thanks. Replied and addressed the comments. Regarding a potential FAC, according to
Wikipedia:Featured articles/By length it would actually only be the thirty-longest FA if it were to pass at the current length ... but I see the point that such a super long thing is hard to review especially as it might become even longer in the future as more science about this is written.
Jo-Jo Eumerus (
talk,
contributions)
06:22, 25 April 2019 (UTC)reply
It always depends on the article, whether excessive length is warranted for the topic or not. The last article I witnessed to fail at FAC just because of length was
National Front (UK), which is much shorther than this one. --
Jens Lallensack (
talk)
21:21, 21 May 2019 (UTC)reply
The end of the humid period appears to reflect the changes in insolation during the Holocene[78] with a progressive decrease thereof leading to decreased insolation gradients between Earth's hemispheres[470] but appears to have been much more abrupt than the insolation changes. – Sentence is very long and difficult to read. I don't understand the last part "but appears to have been much more abrupt than the insolation changes" – this reads to me like "the decrease of insulation was more abrupt than the insolation changes", which makes no sense.
There might be differences between plants at higher versus these at lower latitudes, – perhaps just "differences between plants at higher and lower latitudes"?
Decreases in polar insolation through altered cosmic ray fluxes … – remainder of the sentence does not seem complete, as it becomes a list without connections.
Additional feedback processes may have included the drying of soils and loss of vegetation after decreased rainfall[100] would led to wind-driven deflation of the soils. – "which would led"? --
Jens Lallensack (
talk)
21:21, 21 May 2019 (UTC)reply
Similar changes have been observed on the Adamawa Plateau[484] (Cameroon[466]) – Did you cite [466] just to source the fact that the Plateau is in Cameroon? This is not necessary.
between human expansion in Cameroon and environmental degradation – "Degradation" is always something negative. "Change" would be neutral (a desert is also an environment!). If humans had no influence, than we should use "change" imho. "Degradation" thus implies that humans had an influence, which is precisely what the sentence questiones (no correlation). Thus use "change"?
In the Sudanian and Sahelian savannah on the other hand human activity seems to have had little impact – "on the other hand" indicates that human activity had an impact elsewhere. But no evidence for this was provided in the preceding sentences (just one study that did not find a correlation, and some facts without explicit interpretation in this direction).
This is somewhat complex. Basically, there is an open controversy about how much human activity impacted on the environment in Central Africa and that controversy is not settled. Elsewhere on the other hand evidence for human impact is much more scant. The source cited for this statement is summarizing other research articles.
Jo-Jo Eumerus (
talk,
contributions)
19:03, 23 May 2019 (UTC)reply
Such human migrations towards more hospitable conditions along rivers and the development of irrigation also took place along the Euphrates River, Tigris River and Indus River, leading to the development of the Sumerian and Harappan civilizations. – Sumer started 6500 years ago, before the end of the humid period and much earlier than the Harappan civilization? Furthermore, I think the info that the Harappan civilization used irrigation is outdated, see here for a summary:
[1]
I dunno.
Sumer suggests that the society there started a few millennia later, or at least the urban aspects. Also, the Arabian AHP might not have ended at the same time as the Africa one. I am guessing this is just the problem with linking two separate events with an uncertain chronology but I don't recall seeing any sources that explicitly rule out a connection between climate drying and the onset of Mesopotamian civilization. Regarding the Harappan civilization, is that study the last word on the irrigation question?
The source in the article is from one year later and says The increasingly arid conditions at the end of the African Humid Period forced human agropastoral societies to improve their organization in order to optimize natural resources, in particular freshwater supplies (7). As a result of growing demographic pressure in an environment that was again becoming hostile, Neolithic communities were forced to concentrate in river valleys and to develop irrigation systems. These complex transformations help explain the rise of the Egyptian, Sumerian, and Harappan civilizations that flourished along major rivers such as the Nile, Euphrates, Tigris, and Indus.Jo-Jo Eumerus (
talk,
contributions)
09:57, 30 May 2019 (UTC)reply
@
Jens Lallensack: Hmmm. Well, the article here probably should still say that the end of the AHP is linked to the onset of the Harappan civilization. I am not sure how to separate the "irrigation" aspect; maybe say "often with irrigation" rather than just "irrigation"?
Jo-Jo Eumerus (
talk,
contributions)
13:52, 30 May 2019 (UTC)reply
The article is promoted now. Congratulations! For further improvement, I would strongly suggest to find ways to shorten this article, moving text into sub-articles and such. --
Jens Lallensack (
talk)
14:02, 30 May 2019 (UTC)reply
I'm sorry that I didn't get far yet. Here is the first bunch of points:
It involved changes in Earth's orbit around the Sun, changes in vegetation and dust in the Sahara that altered the African monsoon, the disappearance of much of the Sahara desert which was replaced by grassy vegetation, trees and lakes and the settlement of the former desert by various animals and humans, who survived as hunter-gatherers. – You do not differentiate between causes and effects, why? I would have expected that both are treated separately.
There is kind of a sorting with the cause being first and the effects second. First part is the ultimate cause, second part the feedback effects, third the actual changes and fourth their ramifications.
Jo-Jo Eumerus (
talk,
contributions)
20:56, 16 March 2019 (UTC)reply
Well, I do think that the "interesting" bits needs to stay in, as otherwise a reader unfamiliar with the topic has no idea that there is more to this than a technical article on a climate anomaly thousands of years ago. That necessarily restricts how much of it can be rewritten. Part of the point of a lead section is to hook a reader in to the article.
Jo-Jo Eumerus (
talk,
contributions)
07:17, 25 March 2019 (UTC)reply
I did not mean to remove something, I merely see a prose issue. What about "It was caused by changes in Earth's orbit around the Sun, and involved changes in vegetation …"? --
Jens Lallensack (
talk)
02:58, 25 April 2019 (UTC)reply
It has had profound effects on present-day Africa – as only culture stuff is listed, maybe specify with "present-day African culture"? As Ancient Egypt and the Golden Age myths impacted not only Africa, maybe you can even skip the "present-day Africa"?
My concern with "present-day African culture" is that it's a bit too specific IMO, in terms of timespan. I think that Ancient Egypt should still be considered "Africa". As for the Golden Age myths ... I dunno how to formulate this.
Jo-Jo Eumerus (
talk,
contributions)
20:56, 16 March 2019 (UTC)reply
and had extensive dune fields, many lakes and rivers such – think you need a ";" here instead of the ",". With the latter, it reads like a listing, which misleads the reader.
The African humid period commenced about 14,600–14,500 years ago at the end of Heinrich event 1 and concomitant to the Bølling-Allerød warming, rivers and lakes such as Lake Chad formed or expanded – not especially good with English grammar, but shouldn't this sentence start with "As the African humid period …", or alternatively "with rivers and lakes"?
but the end of the African humid period came about 6,000–5,000 years ago during the Piora Oscillation cold period when the Sahara occupied its present position. – I would start a new sentence here.
which shifted the season during which Earth is closest to the Sun towards Northern Hemisphere summer during the early Holocene – a bit concoluted, lot of stuff put togehter here, not so easy to read. Why not moving the "during the early Holocene" to the sentence "The African humid period commenced …"? Would be more helpful there.
This was not enough to make the Sahara disappear – Suggest "This alone was not enough" for clarity. Otherwise one would assume that it means that the Sahara did not disappear completely.
The terms "Léopoldvillien"[19] and Ogolien [fr] has been applied to the dry period in the last glacial maximum. – These terms are not mentioned again, so I wonder why they are relevant here? Reducing complexity would make it easier for readers.
In addition to drought, glaciers were active in the Bale and Semien Mountains of Ethiopia during the last glacial maximum – I'm confused about the "in addition". To what do drought + glaciers add up? Hostility? What does it want to tell us?
Due to the phenomenon called precession – this is wordy but does not explain anything; I also would not call it a "phenomenon", as it is more of a condition?
This effect was strengthened by the increased summer insolation thus leading to a stronger monsoon that also reached farther north. – This, and the whole paragraph, is basically a repetition of what was already said. Suggest to merge it with the preceding paragraph.
Contrarily, northward transport of moisture during autumn and spring directed by throughs close to Northern Africa has also been proposed to explain the increased precipitation and its underestimation by climate models. – I don't get this
A reduction in open grasslands caused by the African humid period may explain a population bottleneck in cheetahs at the start of the humid period – So they did not move northwards? I thought there was a lot of grass land during the period?
This is going to be tough. This source believes that there may have been less grassland during the AHP. Other sources say it expanded. Seems like at first it may have shrunk; the source does not specify but I made a small change.
Jo-Jo Eumerus (
talk,
contributions)
07:17, 25 March 2019 (UTC)reply
both in Egypt and both feature archeological sites – "featuring"?
The African humid period ended about 6,000-5,000 years ago around 5,500 years before present and after a vegetation decline sand claimed the Sahara which became barren, accompanied by increases in dust export from the now-desert and from dried up lakes. – Long, complicated sentence that is hard to read.
Increased autocorrelation – Again; translate into comprehensible language?
That's a tough one. Even I had to look up "autocorrelation" and it's apparently not something that's easily "translated" as each definition I've seen is just as technically worded; I've stripped it out for the time being.
Jo-Jo Eumerus (
talk,
contributions)
06:22, 25 April 2019 (UTC)reply
calibrated years ago – can this be explained at first mention?
If you wish to submit this to FAC in the future, I would seriously shorten it beforehand. It became too long for a single article. That is ok for becoming GA. --
Jens Lallensack (
talk)
02:58, 25 April 2019 (UTC)reply
@
Jens Lallensack: Thanks. Replied and addressed the comments. Regarding a potential FAC, according to
Wikipedia:Featured articles/By length it would actually only be the thirty-longest FA if it were to pass at the current length ... but I see the point that such a super long thing is hard to review especially as it might become even longer in the future as more science about this is written.
Jo-Jo Eumerus (
talk,
contributions)
06:22, 25 April 2019 (UTC)reply
It always depends on the article, whether excessive length is warranted for the topic or not. The last article I witnessed to fail at FAC just because of length was
National Front (UK), which is much shorther than this one. --
Jens Lallensack (
talk)
21:21, 21 May 2019 (UTC)reply
The end of the humid period appears to reflect the changes in insolation during the Holocene[78] with a progressive decrease thereof leading to decreased insolation gradients between Earth's hemispheres[470] but appears to have been much more abrupt than the insolation changes. – Sentence is very long and difficult to read. I don't understand the last part "but appears to have been much more abrupt than the insolation changes" – this reads to me like "the decrease of insulation was more abrupt than the insolation changes", which makes no sense.
There might be differences between plants at higher versus these at lower latitudes, – perhaps just "differences between plants at higher and lower latitudes"?
Decreases in polar insolation through altered cosmic ray fluxes … – remainder of the sentence does not seem complete, as it becomes a list without connections.
Additional feedback processes may have included the drying of soils and loss of vegetation after decreased rainfall[100] would led to wind-driven deflation of the soils. – "which would led"? --
Jens Lallensack (
talk)
21:21, 21 May 2019 (UTC)reply
Similar changes have been observed on the Adamawa Plateau[484] (Cameroon[466]) – Did you cite [466] just to source the fact that the Plateau is in Cameroon? This is not necessary.
between human expansion in Cameroon and environmental degradation – "Degradation" is always something negative. "Change" would be neutral (a desert is also an environment!). If humans had no influence, than we should use "change" imho. "Degradation" thus implies that humans had an influence, which is precisely what the sentence questiones (no correlation). Thus use "change"?
In the Sudanian and Sahelian savannah on the other hand human activity seems to have had little impact – "on the other hand" indicates that human activity had an impact elsewhere. But no evidence for this was provided in the preceding sentences (just one study that did not find a correlation, and some facts without explicit interpretation in this direction).
This is somewhat complex. Basically, there is an open controversy about how much human activity impacted on the environment in Central Africa and that controversy is not settled. Elsewhere on the other hand evidence for human impact is much more scant. The source cited for this statement is summarizing other research articles.
Jo-Jo Eumerus (
talk,
contributions)
19:03, 23 May 2019 (UTC)reply
Such human migrations towards more hospitable conditions along rivers and the development of irrigation also took place along the Euphrates River, Tigris River and Indus River, leading to the development of the Sumerian and Harappan civilizations. – Sumer started 6500 years ago, before the end of the humid period and much earlier than the Harappan civilization? Furthermore, I think the info that the Harappan civilization used irrigation is outdated, see here for a summary:
[1]
I dunno.
Sumer suggests that the society there started a few millennia later, or at least the urban aspects. Also, the Arabian AHP might not have ended at the same time as the Africa one. I am guessing this is just the problem with linking two separate events with an uncertain chronology but I don't recall seeing any sources that explicitly rule out a connection between climate drying and the onset of Mesopotamian civilization. Regarding the Harappan civilization, is that study the last word on the irrigation question?
The source in the article is from one year later and says The increasingly arid conditions at the end of the African Humid Period forced human agropastoral societies to improve their organization in order to optimize natural resources, in particular freshwater supplies (7). As a result of growing demographic pressure in an environment that was again becoming hostile, Neolithic communities were forced to concentrate in river valleys and to develop irrigation systems. These complex transformations help explain the rise of the Egyptian, Sumerian, and Harappan civilizations that flourished along major rivers such as the Nile, Euphrates, Tigris, and Indus.Jo-Jo Eumerus (
talk,
contributions)
09:57, 30 May 2019 (UTC)reply
@
Jens Lallensack: Hmmm. Well, the article here probably should still say that the end of the AHP is linked to the onset of the Harappan civilization. I am not sure how to separate the "irrigation" aspect; maybe say "often with irrigation" rather than just "irrigation"?
Jo-Jo Eumerus (
talk,
contributions)
13:52, 30 May 2019 (UTC)reply
The article is promoted now. Congratulations! For further improvement, I would strongly suggest to find ways to shorten this article, moving text into sub-articles and such. --
Jens Lallensack (
talk)
14:02, 30 May 2019 (UTC)reply