Talk:Meganeura

Untitled
75 centimeters! Holy crap, I am going to have nightmares.

Big jeans?
The page says: The word Meganeura means “Big Genes”. This is almost certainly incorrect, particularly in view of the naming date; in 1885 nobody has heard of genes yet. AFAIU, meganeura means “big nerves”, but it probably refers not to actual nerves but to the network of air-filled veins in the wings (cmp. insect wing and Neuroptera). My best guess would be “large-veined”, and I changed the page accordingly. Freederick 10:31, 11 January 2007 (UTC)

Pop Culture
At the risk of making the pop culture section larger than the scientific section, should it be mentioned that Davis Schwimmer's character on Friends (a paleontologist) had a reconstruction of a Meganeura as wall art in his apartment? 172.130.4.65 13:58, 6 July 2007 (UTC)RKH

Autochthony thinks mentioning this would be good. 2101z 5.12.2009. 86.151.60.238 (talk) 21:01, 5 December 2009 (UTC)

Respiration
Autochthony writes: the articles states/claims:  -  "However, more recent research indicates that insects really do breathe, with "rapid cycles of tracheal compression and expansion".[3] If correct, then there is no need to postulate an atmosphere with higher oxygen partial pressure". Logically, if modern insects can breathe this way, as appears to be the case from the 'more recent research', which could hardly have been done on fossil insects, then something other than respiration/oxygen availability keeps modern insects from reaching the impressive sizes of Meganeura et al; possibly this may be compeition with birds. Autochthony wrote 2100z, 5 December 2009. 86.151.60.238 (talk) 21:00, 5 December 2009 (UTC)

Obviously it has something to do with climate since birds did not exist in the late carboniferous and would not exist for quite some time, not till after the extinction of dinosaurs. It is changes in climate that not only prevented the megafauna of the Carboniferous from surviving, but also that of the Triassic and other periods. It appears that climatic conditions heeded the large re-growth of any amphibians, reptiles or terrestrial arthropods and allowed mammals, birds and cartiaginous fish to contains the largest species in terms of size. Gravity and air pressure are other parameters which are not mentioned here and Earth's force of gravity is known to not have been constant throughout geologic time. Higher pressure would cause exoskeletons to be at a disadvantage as the force exerted by the outer shells would likely crush the internal organs. This may also be why the largest extant fish species are cartilaginous fish rather than bony fish. 72.39.250.213 (talk) 07:33, 28 May 2010 (UTC)

The role of oxygen content in the reduction of size has been further demonstrated with more recent evidence, as shown in this 2010 study:

The bigger an insect, the bigger the proportion of its body devoted to its tracheal system, which functions like a lung but is far less efficient at large sizes —Preceding unsigned comment added by 72.39.250.213 (talk) 07:53, 28 May 2010 (UTC)

Giant Bugs a Thing of the Past - National Geographic

Amphibians as prey
I could not find a reference to the scientific literature supporting the statement that Meganeura preyed on amphibians. I also can't imagine how anyone would be able to infer that from the fossil record. Living dragonflies capture their prey in flight. This looks like a made-up factoid, so I removed it. — Preceding unsigned comment added by 71.59.208.88 (talk) 22:47, 30 July 2013 (UTC)

Size
The last sentence seems a bit "out of the blue" to me. Could someone with knowledge on the subject elaborate this sentence a bit? Because it's quite conflicting with the other mentioned theories. Maybe adding another paragraph, or have the known theories in a list as a preamble with elaboration under it? 217.121.65.15 (talk) 20:48, 6 December 2016 (UTC)


 * Okay, forget what I said. I got a bit confused by the layout of this section, but the external link provided me with enough explanation. So I decided to do a overhaul of this section myself. Shuffled topics around, created some paragraphs, and made a bullet list of the different theories. I left the text itself intact except a few grammar changes. I hope you don't mind. 217.121.65.15 (talk) 00:01, 7 December 2016 (UTC)

Species?
I'm unable to find if m.brongniarti is a valid species. The website, Fossilworks, states m.brogniarti is a synonym to m.monyi. http://fossilworks.org/?a=taxonInfo&taxon_no=175808 But, is Fossilworks a reliable source for Wikipedia?07:11, 29 January 2020 (UTC)Gabeluna27 (talk)

'Breath(ing) with … cycles of … compression and expansion'.
The following § might infer, without implying (rather only on the issue of respiratory "flight energetics" limiting size growth bounds on the species due to oxygen intake) that the mechanics of birds and these insects follow similar rules – yet birds have unidirection breathing and not, as it seems to say with the ref., 'rapid cycles of tracheal compression and expansion'. Does this implication of two part drawing/releasing of breath hold for agonflies? ….if soshort caveat on the di added, despite the issue at hand indicating the shared evolutional stressors on the condition of their shared 'flightedness' being effected by their respiration.

It seems if such a disparity in breathing type exists it should be logically distinguished here, in as minimal a way possible, or the allusion has a glaring point of misleading contention to the fact of the matter - at least when using the other as a matching category which it would otherwise entail, seemingly wholesale, some mutual situation which both arise from.

“If this hypothesis is correct, these insects would have been susceptible to falling oxygen levels and certainly could not survive in our modeo breathe, with "rapid cycles of tracheal compression and expansion".[6] Recent analysis of the flight energetics of modern insects and birds suggests that both the oxygen levels and air density provide an upper bound on size.”--[[Ustember 2021 (UTC)
 * Do you have a reliable source that supports the position you are outlining here? If so can you supply i to be honest, so I am guessing at what you are attempting to convey.-- Kev  min  § 01:09, 28 September 2021 (UTC)