Wikipedia:Reference desk/Archives/Science/2020 November 9

= November 9 =

When did deciduous plants first occur?
I took at look at the article on deciduous plants, but I don't see anything when they first occured. To be specific, I'm looking for complete seasonal leaf loss. Loss in Dry Season vs. Wet Season is fine (I'm not sure whether that came before or after cold weather leaf loss.Naraht (talk) 02:04, 9 November 2020 (UTC)


 * According to the U·X·L Encyclopedia of Biomes, the first deciduous trees evolved about 180 million years ago. No further source is given. However, the book Eastern Deciduous Forest states (again without source): "Flowering plants, on the other hand, which eventually led to modern deciduous trees, evolved at least 125 million years ago in the geologic period known as the Cretaceous." Since the conventional division in geological periods has the Cretaceous as lasting from about 145 to 66 million years ago, that puts it considerably later. 180 million years ago is in the middle of the Jurassic. --Lambiam 08:04, 9 November 2020 (UTC)
 * The lead of Flowering plant supports the idea flowering plants have first been observed 140 million years ago although I didn't check the source. However the article proper suggests some evidence has been found of them 180 million years ago and some chemical evidence for even older, but I don't know how well that is supported. In any case the lead says angiosperms diverged from gymnosperms about 200 million years ago. However it's unclear to me why that source claims flowering plants are required for modern deciduous trees since as per deciduous trees, there are deciduous Pinophyta/conifers such as Taxodium distichum (bald cypress). See also Category:Deciduous conifers. I think at least some of these meet the OP's criterion of complete leaf drop, e.g. the photo on our article for T. distichum looks like it. BTW, for clarity I'm not saying deciduous conifers evolved before deciduous angiosperms, simply that Lambiam's source's assumption that deciduous trees only evolved with angiosperms seems flawed for at least 2 1 reason s . And if we consider the question, another issue arises.  Nil Einne (talk) 09:36, 9 November 2020 (UTC) 12:24, 9 November 2020 (UTC)
 * The source talks about modern deciduous trees. Perhaps the author puts deciduous conifers in the category "old-fashioned deciduous trees". :) --Lambiam 16:33, 9 November 2020 (UTC)
 * "Conifers are old; they pre-date the rise of angiosperms (flowering plants) by many millions of years. And two deciduous conifers are particularly old, dating back to the mid-tertiary swaps. Taxodium and Metasequoia are remnants of formerly much more geographically widespread groups".  Alansplodge (talk) 09:03, 10 November 2020 (UTC)

Pumping Florida rainwater to dry areas like Texas and Mexico
Is that feasible? If it would take too much energy, what about with using nuclear power?Rich (talk) 18:00, 9 November 2020 (UTC)
 * If it were feasible, why would you think someone before you wouldn't have thought of it? The average price of water is about $1.50 per 1000 US Gallons, per  For comparison, the average price of crude oil is about $40 per barrel, per, at 31.5 gallons per barrel, that's a price of $1260 per 1000 gallons, so it is a bit over 800 times more profitable to move oil by pipeline than water.  There's no way that piping water over long distances would be more efficient than any other means to get water to such places.  It doesn't make any economic sense.  -- Jayron 32 18:38, 9 November 2020 (UTC)
 * ok ok sorryRich (talk) 22:20, 9 November 2020 (UTC)
 * What do you mean by "rainwater" and how do you plan to collect it? Maybe just importantly, why do you think Florida will be willing to give it up or echoing one of Jayron32's point, Texas will be willing to pay a price that Florida thinks is fair? See e.g. [//scholarship.law.tamu.edu/cgi/viewcontent.cgi?article=1058&context=lawreview] which discusses loosely related issues including a dispute between Texas and Oklahoma over water. Nil Einne (talk) 19:26, 9 November 2020 (UTC)
 * BTW, Texas (and Mexico) both have coast lines so seawater desalination sets an upper bound for the price of water, and is an option not requiring Florida to agree if you don't have to worry about energy. [//www.bbc.com/news/science-environment-54723147] [//www.wired.com/story/desalination-is-booming-but-what-about-all-that-toxic-brine/] [//www.youtube.com/watch?v=k__ZNaqgRaQ] Nil Einne (talk) 19:33, 9 November 2020 (UTC)
 * I know very little about Florida's water situation, but I found from War over Water that we have articles on the Tri-state water dispute and Water wars in Florida which seems to emphasise my point on the willingness of Florida to give up this mysterious rain water. If you're already fighting over water within your state, and with neigbouring states, your willingness to give it up to states further away let alone other countries seems likely to be low. Nil Einne (talk) 20:17, 9 November 2020 (UTC)


 * Everything has a price. If someone is willing to pay more for water than for the equivalent mass of oil, it could be feasible. ←Baseball Bugs What's up, Doc? carrots→ 04:31, 10 November 2020 (UTC)


 * In Australia, the Goldfields Water Supply Scheme has, for over a century, piped water from near Perth to the Kalgoorlie area 550 km (340 miles) away. Kalgoorlie's average annual rainfall is around 265 mm, or 10 inches, so without the pipeline living there would be impossible. HiLo48 (talk) 06:29, 10 November 2020 (UTC)
 * Context is everything 1) Much of Texas and Mexico are not particularly drought-stricken. The Yucutan has lovely drinking water.  Limestone filtered.  Great aquifers.  Tons of the stuff.  Most of the Gulf Coast of Mexico has as much rain than Florida.  Tampico gets more rain than Miami.  The really deserty parts of Mexico are places like Sonora and Baja and Chihuaua, and no one really lives there.  The Eastern third of Texas is forested and well watered as well.  2) Taking the shortest route from "Florida" to "Texas" (and not even the "really rainy part of Florida" to the "Really dry part of Texas" is 442 miles from Pensacola to Port Arthur, so a third again as long as your route, which is probably, just barely, economically feasible.  Getting it to West Texas, where it is really dry, is much farther.  Pensacola to Amarillo is like 1000 miles, and Pensacola to Abilene is over 800 miles; Abilene lies on the eastern edge of the deserty part of Texas.  The OP's question, beyond ignoring the economics, also ignores the local geography and shows some rather large misconceptions of what much of Texas and Mexico is like.  -- Jayron 32 12:47, 10 November 2020 (UTC)
 * Much Florida water is requlated to ensure the survival of the Everglades. Rmhermen (talk) 15:32, 10 November 2020 (UTC)
 * What's really needed is to figure out a way to direct rainstorms toward the west. Good luck with that! ←Baseball Bugs What's up, Doc? carrots→ 15:42, 10 November 2020 (UTC)
 * Didn't the Orange Menace suggest to nuke hurricanes? Maybe they can be threatened to take a different course! --Stephan Schulz (talk) 18:57, 10 November 2020 (UTC)
 * I was just asking, guys. I’m sorry if it was a dumb question, but if one holds back on asking questions for fear they are dumb questions, possibly better followup discussion woud be missed out on. In answer to some of your questions to me: it seemed to me, a layman, that florida is getting a lot of rainwater and seawater right now due to numerous tropical storms, and if it the trend continues in the next few years with global warming, florida might need to either be partly abandoned, or sea walls will have to be built, but also: it seemed to me, a layman, that some rainwater would need to be shipped out not just to prevent flooding, but to prevent longterm subsidence. I don’t know all the details, but i thought if global warming gets bad enough, Mexico and even Texas could become largely uninhabitable, i had thought partly from drought. Since I view Mexico an innocent victim of global warming, and the United States as one of the worst causers of it, I feel as an american a responsibility to ameliorate what could happen to Mexico. I don’t know how such an engineering project could be done, that’s why I asked you how and if and (of course)should it be done. Rich (talk) 23:36, 10 November 2020 (UTC)
 * You don't know till you ask. :) ←Baseball Bugs What's up, Doc? carrots→ 15:50, 11 November 2020 (UTC)
 * It's a valid area for blue sky thinking, Rich, but I doubt that the amount of fresh water mere humans would feasibly be able to pipe out of Florida would have any significant effect on its forthcoming over-abundance (mostly of the saline variety) due to the planet's rising sea and storm levels. Incidentally, have you read Paolo Bacigalupi's The Water Knife? Aside from recommending the book itself, I draw your attention to the possibly useful links in the article's 'Major themes' section. {The poster formerly known as 87.81.230.195} 90.200.136.194 (talk) 00:48, 11 November 2020 (UTC)
 * Feasibility always figures into it. Like with Will Rogers' idea on how to do away with German U-boats during WWI: "Boil the ocean!" ←Baseball Bugs What's up, Doc? carrots→ 15:51, 11 November 2020 (UTC)


 * If you need to transport water, you build and Aqueduct (water supply) and let gravity do the heavy lifting (or heavy sinking). But Florida is not only 2,000km away from Texas, but also relatively lower terrain, hence: it would take lots of energy, that could be used for desalination instead (as mentioned above). Houston is not far from the sea and this could work well for them. For the official outlook on desalination, look at the page of Texas Water Development Board: Bumptump (talk) 12:35, 11 November 2020 (UTC)