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This is an old revision of this page, as edited by 69.122.133.58 (talk) at 01:40, 8 June 2009 (→‎This article is biased and plain wrong). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

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Re-write

With the advent of WikiProject Palaeontology, and Portal:Palaeontology, I have to say that this page would benefit from significant work.

I have recently been shocked by how many intelligent adults don't know the difference between Geology, Palaeontology and Archaeology, and think it would be really useful for this article to present a really basic, yet thorough, introduction to the subject.

As such I would suggest that it should take a "summary style", with each section giving a brief overview of a more detailed article available elsewhere for the interested - a little like Cambrian explosion. I would suggest the following structure, and would welcome comment!

  • Introduction: Palaeontology as the history of life. What we study.
  • Brief overview of the Evolutionary history of life, including dates and "identifiable" datum points - e.g. Dinos, humans. Focus on berevity of human existance and the vastness of pre-Dino, and pre-animal, time.
  • Overview of the available evidence.
    • Fossils, with a note on the incomplete nature of the fossil record
    • Radiometric dating
  • History of Palaeo and Palaeo thought.

Suggestions and contributions welcome!!

Martin (Smith609 – Talk) 21:11, 26 August 2008 (UTC)[reply]

I agree that the page needs a major overhaul. Not sure if I get your outline, but I say go for it and we can work it out. Nowimnthing (talk) 12:22, 27 August 2008 (UTC)[reply]

Sources, etc.

Definition

(descending order of merit, IMO)

-- Philcha (talk) 20:35, 17 September 2008 (UTC)[reply]

Cladogram

Thanks for taking the time to improve this article. It's a lot less embarrassing now! Just a little niggle re. the cladogram: at the moment it implies that all tetrapods are either amphibians or mammals, and that all amniotes are mammals. I'm not sure how you want to fix that without making it too complicated! Martin (Smith609 – Talk) 00:18, 20 September 2008 (UTC)[reply]

Finding a cladogram that covers a well-known clade, has a ref, is reasonably brief, isn't too specialised but doesn't over-simplifiy to the point of being plain wrong is difficult.
How much do you know about biostratigraphy? Dating should be the next section, I know only the basic idea of biostratigraphy.
Small shellies is about to go GA. -- Philcha (talk) 07:59, 20 September 2008 (UTC)[reply]
Re the cladogram, I've boldly corrected the problems in Cowen's simplification of the sauropsid sub-tree – convergent warm-bloodedness is the real gold nugget in his presentation.
But could use some help on biostratigraphy. -- Philcha (talk) 08:38, 20 September 2008 (UTC)[reply]
Tetrapods

Amphibians

Amniotes
Synapsids

Extinct Synapsids

   

Mammals

Reptiles

Extinct reptiles

Lizards and snakes

Archosaurs
 ? 
xxx?

Extinct
Archosaurs (cold-blooded?)

xxx

Crocodilians (cold-blooded)

Dinosaurs
 ? 
xxx

Extinct cold blooded dinosaurs

*?*
???

Extinct warm-blooded
Dinosaurs


 ? 

Birds

Hate to be a pain, but the cladogram doesn't sit comfortably with me. I've no easy access to the book, but from my sketchy vertebrate knowledge it looks like the most parsimonious tree is for a single warm-blooded event in the place marked *?*. With any of the others, cold-bloodedness would have to re-evolve. It's just as important to mark the loss of a character as its gain (as I've denoted "xxx").
Also, it could be simplified a little by removing amphibians, if you wanted.
Re. biostratigraphy, I don't think there *is* much to know other than the basics of matching faunal assemblages across continents, and the potential for problems if the species used have longer ranges than thought. I'll take a look at its article and see if I can add anything interesting. Martin (Smith609 – Talk) 13:26, 20 September 2008 (UTC)[reply]
Re "cold-bloodedness would have to re-evolve", that's a strong possibility – (a) it's what the ref for the cladogram says; (b) see text & refs at Physiology_of_dinosaurs#The_crocodilian_puzzle_and_early_archosaur_metabolism (yes, cleaning that up is on my to-do list) – whichever way you interpret Triassic archosaur metabolism, you get some puzzling consequences. -- Philcha (talk) 07:58, 21 September 2008 (UTC)[reply]
If you can help with biostratigraphy, I'd be grateful. To me it looks as much fun as tax returns. -- Philcha (talk) 07:58, 21 September 2008 (UTC)[reply]
If that's what the ref for the cladogram says, then that's what the cladogram here should say. It's bogus to mark the addition of a character without also noting its loss whereever it occurs.
I'll put in a brief summary of biostrat. Martin (Smith609 – Talk) 13:07, 21 September 2008 (UTC)[reply]
Cowen does not try to explain the puzzle, he merely says that warm-bloodedness must have arisen at one of these 3 points in the archosaur-dinosaur-bird lineage, and notes that it's an example of convergence. -- Philcha (talk) 13:50, 21 September 2008 (UTC)[reply]
I've undone the addition of "possible loss of warm-bloodedness" to the cladogram. The source (Cowen) does not include these points; the choice of a point where warm-bloodedness evolved determines where it might have been lost, e.g. if all non-avian archosaurs were cold-blooded then there is no point at which warm-bloodedness might have been lost. In fact the loss of warm-bloodedness only becomes necessary in this cladogram if one adopts the hypothesis that warm-bloodedness arose in basal archosaurs. There are reasons for for suspecting that at least some basal archosaurs, including the ancestors of crocs, were at least somewhat warm-blooded, but that's outside the scope of this article - for example it is discussed at Physiology of dinosaurs.-- Philcha (talk) 07:41, 26 September 2008 (UTC)[reply]
Then this cladogram is a terrible example of how phylogenetic trees work. Assumptions about where a trait has been lost are an essential point in any tree and I'd consider it deceptive not to include it. Either all the discussion here needs summarising in the figure caption, or you need to find an alternative cladogram with a trait that isn't contraversial - powered flight, say. Martin (Smith609 – Talk) 13:35, 26 September 2008 (UTC)[reply]
I don't think there's anything wrong with the cladogram per se. It looks to me like it's the "warm-bloodedness" bits that are bothering you. Even so, I don't see what the big problem is - modern birds are warm-blooded, no-one seriously suggests that basal amniotes or basal sauropsids were warm-blooded, and that leaves just the options in the cladogram - which does not take sides. -- Philcha (talk) 15:41, 26 September 2008 (UTC)[reply]

Comments

Sorry not to work on the biostrat earlier, my internet went down. Criticisms:

Sources of evidence

Dating is duplicated in "sources of evidence" - I'm not sure whether this is intentional but I suspect it could be removed here.

Moved it to "Estimating the dates of organisms", what do you think? -- Philcha (talk) 19:29, 21 September 2008 (UTC)[reply]
Better. Martin (Smith609 – Talk) 20:43, 21 September 2008 (UTC)[reply]

Overview of the history of life

There are an awful lot of numbers in the potted history of life; maybe you feel they are essential but I find them overwhelming. You should stick to either numbers or period names throughout; consider "hard parts that fossilize easily until about 548 million years ago. The earliest modern-looking bilaterian animals appear in the Early Cambrian, a" - most readers will have no idea if that is a 10 or 100 million year gap.

Give both where possible? -- Philcha (talk) 19:29, 21 September 2008 (UTC)[reply]
Then the dates would take up a huge proportion of the text. I would be inclined to re-write it in the style of my lead for Evo Hist of Life. Martin (Smith609 – Talk) 20:43, 21 September 2008 (UTC)[reply]
You're right about the scope for confusion. But if we're trying not to confuse non-specialists, dates are more important than names - I remember as a kid being frustrated by all those names whose order I didn't yet know by heart; and I still can't remember boundary dates for the Precambrian eras. IIRC you wanted to emphasise how long the full story is and what Johnny-come-latelys we are.
See new draft at User:Philcha/Sandbox/Paleontology. -- Philcha (talk) 22:37, 21 September 2008 (UTC)[reply]
It may not be necessary to include a number for every single point; key points such as the start of the Cambrian, formation of Earth, etc are important, but strategic use of "Soon afterwards" could cut out a lot of the digits, and other points don't necessarily need a number if they're in chronological order. Martin (Smith609 – Talk) 02:46, 22 September 2008 (UTC)[reply]
I've looked and don't see which dates to omit, especially from the point of view of non-specialists who don't know the timescale well or at all. -- Philcha (talk) 17:39, 23 September 2008 (UTC)[reply]

I take a strong dislike to the phrasing "evolved all over the world" re humans - this suggests to me that they evolved independently all over the world. In a way this discussion is moot - they must have come "out of Africa" at some point, whether or not it was 200,000 years ago.

No fair partial quote - the full text is "whether modern humans evolved all over the world from existing advanced hominines"! Like it or not, Wolpfoff is still pushing the Mutli-Regional Hypothesis of the transition from H. erectus to H. sapiens. AFAIK No-one disputes that H. erectus originated in Africa, but then colonised Asia from Beijing to Indonesia ("Peking Man" & "Java man"). -- Philcha (talk) 19:29, 21 September 2008 (UTC)[reply]
The phrasing still suggests the former to me. The debate is about the degree of inter-breeding, not the place of origin. I'd take the easy path and just not mention the controversy, as you don't have room to explain it. Martin (Smith609 – Talk) 20:43, 21 September 2008 (UTC)[reply]
Emphasised "modern humans" at at User:Philcha/Sandbox/Paleontology - does that help?
Can't omit the biggest single current controversy about human evolution. -- Philcha (talk) 22:37, 21 September 2008 (UTC)[reply]
To me, it doesn't seem like an interesting question. If you must keep it, a rephrasing would help : maybe something like
There is a long-running debate about whether all modern humans are descendants of a single small population in Africa, or whether a high degree of interbreeding resulted in H. sapiens increasing in intelligence at a constant rate worldwide" Martin (Smith609 – Talk) 02:46, 22 September 2008 (UTC)[reply]
Good point about interbreeding. OTOH I'd avoid "increasing in intelligence" as there's a separate debate about a possible Cro-Magnon "great leap forward" 40,000 yrs ago, based on apparently sudden higher culture. -- Philcha (talk) 17:39, 23 September 2008 (UTC)[reply]

Mass extinctions

"mass extinctions have sometimes accelerated the evolution of life on earth." - how has this been quantified? Needs a strong suporting reference.

Following sentence has 2 refs which cover whole para. -- Philcha (talk) 19:29, 21 September 2008 (UTC)[reply]
It's good practise to place a reference by each fact; otherwise the work of later editors may distort the link between source and fact. In any case, it's still not completely clear what you mean by "accelerated evolution", and the abstract of the ref I can access doesn't hint that it addresses the rate of evolution. A rewording at the least is in order, I think. Martin (Smith609 – Talk) 20:43, 21 September 2008 (UTC)[reply]
The 2nd sentence explains the first, and both refs are relevant to both.
"competition still may have been important in producing the rise-and-fall pattern through suppression of evolution within replacement taxa; as long as the large carnivore ecospace was filled, the radiation of new taxa into that ecospace was limited, only occurring after the extinction of the incumbents" (Van Valkenburgh ­ 1999). Benton says much the same about the dinos not really getting going until the Tr-J extinction eliminated a lot of archosaurian competitors. -- Philcha (talk) 22:50, 21 September 2008 (UTC)[reply]

"The fossil record appears to show that the gaps between mass extinctions are becoming longer and the average and background rates of extinction are decreasing." I don't think there's statistical support for this; it's certainly not widely enough accepted for a place in this article. The explanations are very unclear, too.

See the ref.
Which specific points do you find unclear? Am I assuming too much prior knowledge? -- Philcha (talk) 19:29, 21 September 2008 (UTC)[reply]
Reading the ref, the first point it makes is that the pattern observed is an artefact. Again I don't think it's profitable to confuse the readers by presenting them with a trend that's mostly artefact, without at least introducing it as an example of problems in palaeontology. Martin (Smith609 – Talk) 20:43, 21 September 2008 (UTC)[reply]
Which ref says the pattern is an artefact?
The 2nd bullet is about an artefact, and describes it as an example of problems in palaeontology. -- Philcha (talk) 22:50, 21 September 2008 (UTC)[reply]
To paraphrase the first point in Norm McLeod's "Extinction!" web page. Martin (Smith609 – Talk) 02:47, 22 September 2008 (UTC)[reply]
McLeod doesn't state that the decline is an artefact, he offers 3 possible explanations, of which one is "it's an artefact". -- Philcha (talk) 06:33, 22 September 2008 (UTC)[reply]

History of paleontology

The first para of the history section reads like trivia - a collection of unrelated and context-free facts.

Virtually copied from lead of History of paleontology, a GA. I suspect initial steps in most sciences look that way - I'm familiar with the ancient Greek philisophers from Thales to the Eleatics and Pythagoras an dDemocritus, so've I've seen the fragmentary and speculative beginnings of modern science, which used to be called "Natural Philosophy" (when I was at Glasgow U., that's what the Physics dept was called, and Latin was Literae humaniorum!). -- Philcha (talk) 19:29, 21 September 2008 (UTC)[reply]
Then an introductory paragraph saying something like "Palaeontology took a while to become established, even though early thinkers had noticed aspects of the fossil record" would put the factoids in context. Martin (Smith609 – Talk) 20:43, 21 September 2008 (UTC)[reply]
Intro sentence added - see what you think. -- Philcha (talk) 22:50, 21 September 2008 (UTC)[reply]

(general)

And I guess you've left the lead to last?

Of course! It's 15-minute job at most once the content's stable - Kimberella and Opabinia took under 10 each. -- Philcha (talk) 19:29, 21 September 2008 (UTC)[reply]

Martin (Smith609 – Talk) 17:53, 21 September 2008 (UTC)[reply]

You may also want to change the image captions to make it clear why the images are relevant to the text. I'm puzzled as to how the location of a bee's nectar sacs has a palaeontological implication, for instance! Martin (Smith609 – Talk) 20:45, 21 September 2008 (UTC)[reply]

See new caption at User:Philcha/Sandbox/Paleontology -- Philcha (talk) 22:51, 21 September 2008 (UTC)[reply]
Great. Yanocodon could use a similar treatment while you're at it. Martin (Smith609 – Talk) 02:32, 22 September 2008 (UTC)[reply]
"during the age of dinosaurs" instead of numerical date? My greatest concern about that is that some later Mesozoic mammals were bigger, see Evolution of mammals#Expansion of ecological niches in the Mesozoic -- Philcha (talk) 17:44, 23 September 2008 (UTC)[reply]

Review

I'll look at this in detail later, but glancing through I found two errors. Tim Vickers (talk) 17:00, 5 November 2008 (UTC)[reply]

First line

I've embedded the link to paleoecology in the first line; it seems to be an appropriate link that could not use fewer of the words in the sentence. Secondly, the parenthesised version doesn't read well and I think that it is a little clumsy, especially for a first line. --203.129.58.2 (talk) 07:00, 23 February 2009 (UTC)[reply]

OK. Tim Vickers (talk) 19:01, 23 February 2009 (UTC)[reply]
Oh, I see you're discussing it here. Go ahead and revert my edit until consensus is reached. I disagree that the change (Vickers' version) is as clumsy as the original, which is just too long and difficult to navigate, in my opinion. I'm not enamored of the Vickers' version, either. Maybe we could find a better wording? --KP Botany (talk) 06:08, 24 February 2009 (UTC)[reply]

"Preparation" image

Image File:Europasaurus Praeparation.JPG has been added just below the lead image. I'm not sure this is a good place for it, as it is overshadowed by the lead image. The article is already quite lavishly illustrated by WP standards, and I think adding images would turn it into a WP:GALLERY. Personally I think the preparation image competetes with the one that shows a paleontologist looking like a miner as he chips bones out of a rock face - both highlight the amount of hard, unglamorous work required before anyone gets to have fun theorising. --Philcha (talk) 09:39, 1 April 2009 (UTC)[reply]

This article is biased and plain wrong

biased in favor of "evolution myth". Does not cite that the world is no more than 6000 years old. —Preceding unsigned comment added by 69.122.133.58 (talk) 01:15, 8 June 2009 (UTC)[reply]

Removing a flag without reaching a fair concensus is a violation of Wikipedia policy!!!

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