Talk:Predation/GA2

GA Review

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Reviewer: RockMagnetist (talk · contribs) 19:33, 15 September 2018 (UTC)[reply]

Comments on content

Many thanks for taking this on, and for your comments below. I'll reply to the comments below individually, as I work them into the article. Chiswick Chap (talk) 07:09, 16 September 2018 (UTC)[reply]

Drive-by comments you never talk about persistence hunting or persistence predators (the only one that comes to mind is humans); the way you word it, it's not very clear how lunge feeding is a form of pursuit predation; and why's it called Related strategies if it's just about scavenging? User:Dunkleosteus77 |push to talk 01:09, 20 September 2018 (UTC)[reply]

Fixed all three of these.

Persistence hunting isn't limited to just humans. Looking a little into it, killer whales also do it User:Dunkleosteus77 |push to talk 23:45, 29 September 2018 (UTC)[reply]

I have again searched the literature, and am unable to find any reliable sources which make that claim. Chiswick Chap (talk) 09:00, 30 September 2018 (UTC)[reply]

Looking a little more, we have wolves and African wild dogs, with this source, as cursorial predators (which is a synonym) in a chapter comparing ambush with persistence predation. This talks about the energy costs in African wild dogs. Back with the orcas, there's this which describes persistence behavior of a pod on a sperm whale, though never explicitly says it in those words. A prehistoric example are running hyenas. A non-mammalian example are some spider species according to this, this, this, and several other sources I'm seeing User:Dunkleosteus77 |push to talk 17:14, 30 September 2018 (UTC)[reply]

Cursorial just means running when applied to predators; they are mostly pursuit predators but ambush predators that run are also covered by the term. Persistence predation is, by the way, impossible for spiders as they need to stop to breathe. Chiswick Chap (talk) 18:13, 30 September 2018 (UTC)[reply]

The one about wolves, "As cursorial predators, they may chase prey for kilometers," the one about African wild dogs, "African wild dogs (also referred to as dogs) have been described as the ultimate cooperative persistence predator" User:Dunkleosteus77 |push to talk 19:38, 30 September 2018 (UTC)[reply]

Used the Nature source, thanks. Chiswick Chap (talk) 20:09, 30 September 2018 (UTC)[reply]

Definition

I recommend having a Definition section, including some of the challenges. For example, some people use other definitions, such as that in Lafferty and Kuris: "a natural enemy that feeds on more than one victim." In that scheme, a micropredator like a mosquito is a predator, whereas in the "kill and eat" version it's a parasite. And is an herbivore a predator? Browsing the web, I found a variety of responses including: yes, it's a predator that eats plants; no, because plants are primary producers; and no, because herbivores don't necessarily kill plants. Unfortunately, I couldn't find very reliable sources for any of these points of view, but you probably know the literature better. Also, there is a spectrum of behaviors between parasitism and predation, and it's difficult to draw the line between them (see this source). I think that was the sort of thing you were trying to do with the reference to consumer-resource models, but this section should be readable by a high school student and should have plenty of concrete examples.

I have added, cited, and illustrated a discussion of why definitions are difficult. We obviously don't want to make the discussion in this early section too academic, however.

I agree. You're very quick to respond! I'm going to finish my first pass through the article before looking at the changes. RockMagnetist(talk) 20:19, 16 September 2018 (UTC)[reply]

Strategy section

The introduction to this section is doing three things: defining predation ("Predators kill and eat other organisms, often but not always other animals"), saying something about their ecological classification (consumer-resource models) and introducing the subsequent subsections on strategies. These don't mix very well.

Have cut the consumer-resource bit, and continued your rewrite (thank you).

Looks much better. I have moved some stuff out that wasn't part of the summary. One statement ("ambush predators are necessarily solitary") makes sense, but the source doesn't even mention ambush predators. It would be nice to find a good source for this statement (or exceptions, if not true). RockMagnetist(talk) 16:32, 18 September 2018 (UTC)[reply]

I've drawn a blank on this one. The statement appears to be assumed to be true without discussion in many sources.

I wish I had a dollar for each time that has happened to me. RockMagnetist(talk) 02:48, 19 September 2018 (UTC)[reply]

I think that the distinction between social and solitary should be represented as two strategies, and not part of a classification of heterotrophs.

I've cut the mention of heterotrophs, separated out the social/solitary distinction, and shown how it cuts across the pursuit/ambush classification.

A more formal discussion of consumer-resource interactions, if any, should be left for the ecology section.

Fair enough, I've removed it.

Pursuit predation: I reorganized it a bit to separate independent topics: a general statement, some info on its taxonomic range, a bit of predator-prey coevolution on land, and baleen whales. The first paragraph is copied from the lead of Pursuit predation, and it's so obvious it's hardly worth stating. I recommend adding a bit more detail from Pursuit predation#Strategy.

Thank you. I guess obviousness is relative (high school and all that). I've extended and rewritten the section from a new source.

Ambush predation: clearly, a cougar is not an example of sit-and-wait; it's stalking, which seems to be either classified as a kind of ambush predation or something in between ambush and pursuit. As with pursuit predation, a lot of this section is copied from the lead of the main article and it's not very coherent.

Have removed the cougar from the examples, rewritten the section from a new source, and added a section on a related strategy, ballistic interception.

Specialization section

Diet and behavior: All the sources in this section are primary. In particular, the Pulliam (1974) paper is just a theoretical prediction; is there any evidence to support it?

Added 'predicted' and evidence with ref.

Diet and behavior, second paragraph: None of the citations at the end of the paragraph have anything to do with the content.

Replaced refs.

Physiology: The sentence about sugar to amino acid transport is rather mysterious. It would help to add an explanation of why this difference occurs.

Glossed.

Ecological role section

Trophic level: Little of this content, in particular the examples, seems to come from the cited source. That also goes for the maximum number of levels, and since that information isn't really needed here, I removed it.

Yes. Tidied it up, added refs.

Population dynamics: In the figure, the predator and prey populations are not periodic! God knows what equations it actually solved; the original data have been removed from the German Wikipedia. I have substituted an illustration with periodic fluctuations.

Ah, a bit more explanation is needed. The L-V model has been extensively researched and has many mathematical variations. With just 2 species, no migration, no age structure, and no seasons it predicts periodic oscillations, with the predator 1/4 of a cycle behind the prey. With any of these constraints relaxed, it mostly predicts wildly chaotic oscillations, as happen in reality, which is why I'd much prefer the other figure. It's easy to see that if predator numbers become very small (ecologists used to joke about the atto-fox problem, 10^-18 of an individual) then extinction and the end of oscillations is the result. There's an enormous literature. I've added a brief account of the field explaining these factors, with further refs. Chiswick Chap (talk) 08:43, 1 October 2018 (UTC)[reply]

It's good that you added more material, because my other problem with this section was that it was too simplistic. (Unless you only care about spiders!). However, I still object to the previous figure because there is no way of knowing which of the many variants it represents. It would be even better if someone were to generate some curves and actually say what equations were solved with what parameters. RockMagnetist(talk) 15:25, 1 October 2018 (UTC)[reply]

Thanks. Yes, I was wondering about trying to make such a thing. It's a bit out of scope of the GAN but I'll look into it sometime. I can live with your choice of image for now. Chiswick Chap (talk) 15:29, 1 October 2018 (UTC)[reply]

RockMagnetist Well I've surprised myself, done dozens of L-V model runs. I've uploaded one of them, and recorded the parameter settings in the filename so they can't get lost. I thought about overlaying two plots but there'd be a mass of closely-spaced lines there which would be confusing and hard to read. As you can see the oscillations are not simple sine waves, nor do they repeat exactly each time - the starting conditions for each iteration are the stopping conditions for the previous one, so things get a bit chaotic. I've also added a little history, and another issue with the L-V model. I'd say we have a full and rich section now, far beyond the 'main points' that GA requires. Chiswick Chap (talk) 21:10, 2 October 2018 (UTC)[reply]

Once again, we have converged. I was not satisfied because it was very theoretical, and a very artificial theory at that. I have added material that emphasizes the real world, clarifies the importance of cycles (restricted to the North) and speaks about stabilizing factors. I really like your addition of the pelt data, and I think the model output isn't really needed now. RockMagnetist(talk) 22:42, 2 October 2018 (UTC)[reply]

OK. I hope we can now complete this GAN swiftly. Chiswick Chap (talk) 07:03, 3 October 2018 (UTC)[reply]

Yes, it should be quick now. The hard part was satisfying myself that the coverage is broad enough for a subject that is itself very broad. The other parts will be a cakewalk. RockMagnetist(talk) 00:35, 4 October 2018 (UTC)[reply]

Coevolution with prey section

Antipredator adaptations: I think this should be made into a separate section. After all, prey redirects to this article, so it should get a top billing. Also, this is another example where it would be better to use a broad secondary source to organize the coverage. In this case, that source is Caro. Its TOC outlines some basic types of adaptation like detecting predators (vigilance), avoiding detection, signalling unprofitability, etc. See also the organization in anti-predator adaptation. I'm not saying you should add a lot of new material, just make sure there are some representative sub-headings and a little material on each type of defense.
Antiprey adaptations: A lot of this should just be a new subsection, Camouflage, in Specialization.
What is left of this section should discuss coevolution for both predator and prey at once. For example, prey get faster, so predators get faster, etc. It would also be good to say something about relict adaptations (e.g., North American pronghorns) and "naive" populations that are decimated when a new predator arrives suddenly. Also, adapting to predators has fitness costs for prey.

Not sure I agree with your thesis here. The whole section already is about coevolution; the adaptations of prey against predators, and of predators against prey, are very different in character and are already each dealt with in separate sections. Camouflage is one mechanism; mimicry is another; aposematism is a third; signalling such as by mobbing and stotting is a fourth: I don't see reason to call all of these 'camouflage', they are rather all anti-predator adaptations.

We *could* split these 'adaptations' sections into subsections, but it's worth pointing out that we are already well down in the hierarchy: Predation -> Coevolution -> Anti-x adaptations. Antipredator adaptation is already and rightly a separate article, with many sections; I'd not think it necessary or appropriate to duplicate its structure here. Same goes for Camouflage and Mimicry.

No, I mean that Specialization is really about anti-prey adaptations, and Antiprey adaptations should be folded into it. And it is this subsection that is mostly about camouflage. I'm suggesting that Antipredator adaptations should become a top-level section. RockMagnetist(talk) 03:19, 24 September 2018 (UTC)[reply]

Sorry, I wasn't as clear as I could have been at midnight. All antiprey and antipredator adaptations are part of the coadaptation process, part of the long-term coevolution of predator and prey. Therefore, both belong in the coevolution chapter. "Coevolution with prey" is like one hand clapping; if predators coevolve with prey, well, prey coevolve with predators. You are right that all predator specializations are coevolutionary. Chiswick Chap (talk) 07:41, 24 September 2018 (UTC)[reply]

I think it's better to separate the predator and prey adaptations for a couple of reasons. First, most of the sources present the information separately; in fact, a lot of the predator adaptations are included in discussions of their foraging behavior. Second, the sources I have found on predator/prey co-evolution basically say that it is asymmetric (since a predator often can choose more than one prey species and doesn't die if they fail to catch a given creature) and sometimes the evidence for it is not clear. So it makes sense to discuss the adaptations separately and then have a brief discussion of coevolution. RockMagnetist(talk) 15:56, 24 September 2018 (UTC)[reply]

OK. I've added some subheadings and one or two images. Chiswick Chap (talk) 17:41, 24 September 2018 (UTC)[reply]

I sense a little frustration in a recent edit summary, so I'd like to clarify my goal here a little. I'm not looking to "copy every bit" of Antipredator adaptations into Predation, but I don't think that a couple of paragraphs can adequately summarize the subject. What I found initially looked more like a random sample with a bias towards coloration. That is where secondary sources are really useful for providing balanced coverage and an organizational scheme. I want to add a bit more on group defenses and add a couple more sentences to each of the last two subsections, and I'll be satisfied.

OK. Chiswick Chap (talk) 20:50, 26 September 2018 (UTC)[reply]

Large images

I think the two large images (wolves and riparian willows) should not be beside text unless they are considerably smaller. Depending on the size of my browser window, I see lines as narrow as two words, which is ridiculous. Better to put them above or below the text and center them.

Done.

Secondary sources

On the whole, this article is well written, well organized and well sourced. However, sometimes it seems like a list of examples, and it's hard to know how representative they are; I keep finding important topics that are missing. I think it would help if secondary sources were used more. These are the sources that I consider secondary with a reasonable breadth of perspective on predation, along with the number of citations in parentheses: Stevens (5); Schmitz (1); Janzen (2); Beauchamp (1); Velicer & Mendes-Soares (1); Royal Sask. Museum (3); Bond (1); Bengtson (1); Kelly (1); Barbosa and Castellanos (0); Curio (0). Of course, my choices are debatable, but I think that if they were used more, it would make this article seem a little more coherent and I'd have more confidence both that it is not original research and it satisfies the breadth of coverage requirement.

I have upped the use of these secondary citations, and added more. They are far from being the only reliable and broad secondary sources in the article: for instance, Cott's range is encyclopedic. The primary sources have mainly been used for broad general (secondary) statements about predation, from their introductory sections. There is no original research in the article.

The article's heading structure, spanning strategies, specialization, coevolution, ecology, evolutionary history, and human society is certainly "broad" and together with the numerous secondary citations makes it clear that the article covers "the main points" as required. I have made several small additions from a range of sources but have not discovered any major subtopics previously unmentioned.

Examples are introduced throughout for three purposes: to illustrate the main mechanisms described; to indicate alternative or specialised mechanisms; and to sketch out the taxonomic range of each mechanism.

Sorry it has taken me so long to reply. I realized that it was not very useful to state my request in such broad terms, so I decided to illustrate the idea on the section on foraging. It was interesting to see that you were converging on the same idea! By building the section on analyses by secondary sources such as Kramer, we both headed to a more comprehensive view of how predators behave. Now that the section is divided into subsections based on the stages of foraging, the diagram is redundant, and I have removed it because it has poor typesetting. RockMagnetist(talk) 04:29, 23 September 2018 (UTC)[reply]

By the way, you make a good point about using the introductions of primary sources as secondary sources. Also, I have nothing against examples, by the way, as long as the big picture is taken care of. RockMagnetist(talk) 04:29, 23 September 2018 (UTC)[reply]

Thank you. I think we have converged on an admirably complete and well illustrated article, by the way. Chiswick Chap (talk) 10:28, 23 September 2018 (UTC)[reply]

I'm glad you like the way this is going. I haven't mentioned illustrations much, but you do a nice job finding good-quality illustrations that provide meaningful support to the text. RockMagnetist(talk) 20:38, 23 September 2018 (UTC)[reply]

Checklist

O.k., time to tick off all the criteria:

It is reasonably well written.
a (prose, spelling, and grammar): b (MoS for lead, layout, word choice, fiction, and lists):
It is factually accurate and verifiable.
a (reference section): b (citations to reliable sources): c (OR): d (copyvio and plagiarism):
It is broad in its coverage.
a (major aspects): b (focused):
It follows the neutral point of view policy.
Fair representation without bias:
It is stable.
No edit wars, etc.:
It is illustrated by images and other media, where possible and appropriate.
a (images are tagged and non-free content have fair use rationales): b (appropriate use with suitable captions):
Overall:
Pass/Fail: