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Yes, that's reasonable. I believe it would be an extension of Newton's original formulation for thin shells, but it's simple enough. You can think of any spherically symmetric planet as an onion, with lots of concentric shells. 🙂

Except that 'Present Reptiles' are not descended from dinosaurs. The lineages that were to become lizards & snakes, turtles & tortoises, the tuatara and the crocodilians had all split off from the sauria/archosaur line before dinosaurs were a thing..

If it were absorption within the atmosphere that energy would be added to the atmosphere. It isn't absorption. This appears to be the correct option. As I understand it gaseous Sulphur Dioxide is the precursor to droplets of sulphuric acid that are reflective to sunlight. Being initially gaseous probably makes it easier to get pushed high in the atmosphere by volcanoes and for the resulting droplets to linger there, up to 2 years and global in effect. Human sources ie from fossil fuel burning rarely make it that high and have residence times of a few days and is more regional in effect. From NASA - This source doesn't specify the altitude of the clouds, but sounds like it has a reflective cooling effect. Regarding the initial question(s) - First, we don't know how to get volcanoes to erupt on demand or continuously. There are proposals for deliberately adding sulphate aerosols to the stratosphere but with (usually) aircraft, not via volcanoes. Sulphate aerosols aren't dust. Not sure dust is such a highly significant factor - probably doesn't linger long enough. But, to echo MigL, massively increasing volcanic activity seems counterproductive. The cooling effect of aerosols depends on the rate you keep adding, whereas global warming is dependent on the accumulated total of CO2 (over the timescales that matter). It doesn't fix the cause, just masks the effects - and the consequences are more complex than simply reducing global warming, ie may induce significant unwanted regional climate changes. My view is that - given existing climate politics - anything gives the illusion that we can keep burning fossil fuels at high rates and avoid the climate consequences is unhelpful - even where those attempts are sincere. Whether intended as an adjunct to commitments to building an abundance of clean energy and reducing emissions it will be used by opponents - and the apathetic - to reduce those ambitions.

Sulphates form compounds at altitude that are especially good at reflecting solar radiation (you'd have to look it up, but there's some sort of scattering index that indicates the relative degrees of scattering and absorption - I'm a little rusty on this). Also, they make good condensation nuclei. You will recall that diffuse water vapor is a GHG (and CO2 effect magnifier), but condensed droplets (i.e. clouds) increase albedo and reflect radiation. That's why there's an anomalous cooling trend (or rather, flattening of the global warming trend IIRC) during the decades 1940-1970s, due to a massive escalation in burning of high-sulfur varieties of coal. As soon as this was curtailed, as governments started dealing with the acid rain problem, that cooling effect went away.

It is my opinion that words themselves are worthless without the world of meaning behind them. It's what it means what's been, I'm sure, essential in human evolution. Long-distance trade, collaboration, etc. would have been impossible without the phatic function of language. Having others know the communication line is open even if you didn't completely understand the full import that they're trying to get across is a priceless function of language. I learnt that word, as usual, by carefully listening to others. I wouldn't have understood it by just reading a book. Thanks for appreciating...

Glad I've asked. Learned a new word, phatic.

Perhaps, but what does it mean? I honestly don't understand semantics of this word combination. For example, I don't know if there's anything wrong with smelling with my mind's nose what my spleen feels. And if there's nothing wrong with it, can I smell nothing but other spleens?

Yes, that's the general idea.

No. Delete the lower 'Birds' and replace with 'Dinos'. Delete the extraneous 'Dinos' line. Best would be to replace 'Reptiles' with 'Sauria' but I guess that's more for the purist than the common folk.

Another thing to keep in mind is that evolution is not purpose-driven. I.e. things do not start to develop because they might be beneficial. Mutations are random and depending on the starting point, there are certain constraints to how much and in which direction a body plan can change without causing problems.

Everything has a cost/benefit. A bigger ribcage or other protection means more weight and less flexibility. More weight means slower movement and/or more calories required. What would be the point of protecting the digestive system if you starve?

Economy. For animals that need to move, sometimes very fast, the weight of bones is a serious consideration. The brain gets most of the bony protection, because even a slight injury to the brain can be fatal. Then the heart and lungs - particularly from behind, where predators are most likely to attack. The gut and stomach get a fatty pad, and a layer of muscle. There a certain amount of flexibility in the abdomen; malleable soft tissue is better able to withstand blows and pressure than the delicate lungs.

One way, in theory, is if the group whom you benefit consists of your close relatives with whom you share genes. By benefiting them you help them to propagate their genes, some of which are your genes. Thus, you help them to propagate your genes including the genes responsible for this trait.

It did. Example: tortoise.

Nowhere. They could have said “underwent oxidation readily”, which in my view would have been better English. It’s just a qualitative statement about what they observed.

I’m guessing people with respiratory issues would love this. Like Seattle residents during the forest fires this past summer. What do mean “we”? I personally sacrificed twice as many last year as compared to a decade ago.

Er, well, mastodons, sabre-toothed tigers, etc. appeared about 40m or more years later, from the Miocene onwards. The mammals that existed at the end of the Cretaceous were indeed small and shrew-like.

Evolution is changes in allele frequency within a population over time. It would be your children and their children that continue to evolve.

swansont You are totally wrong. First, it's just present science BELIEF that axial tilt and the length of the day are not constant, and had different values in the past. The Menorah Matrix PROVES that it is not coincidental and it was always the way it is because a TON of other mathematical patterns confirms it. Picada Please, read the Menorah Matrix before state that "The Menorah Number System is not based on Base10". You are wrong. Period.

Adam always be suspect of what someone tells you about evolution unless they were present sixty million years ago to note the changes in person and relay them to you from direct experience Scientists who try to infer big picture clues from tiny snippets get it wrong sometimes, they update those findings new in updated studies every new decade I just spent fourteen years in one thread in the biology forum here, coral growth vessels thread, convincing scientists that micro reef systems weren't fake They threw all manner of angry denial, scholar links and proofs to the contrary (exactly like evolution debates go) at me since 2009, only to relent finally yesterday Your intuition shouldn't be discounted: the evolutionary link between extant animals and dinosaurs isn't hard to fathom given today's genetic lineage tracing abilities The link between humans and dinosaurs is a massive chasm of guessing no form of authoritative writing or chart posting will ever seal Scientists will fill in the gaps for the portions they don't know, haven't experienced, that's the human portion of the matter. We don't get to know the answer you seek We get to guess at it, and present it to you yet again as indisputable fact that's the inseparable human condition in the matter If you were told that scientists aren't quite sure yet how that leap was completed, and that modes presented as fact today will just change/ evolve in fifty years as science progresses but we can't say definitively how it works now, that'd be fact. Plausible potential options have been presented to you here but not sealed fact I just undid fourteen years of sealed fact by linking YouTube videos, sometimes a little persistence works to undo the going rules of a given decade.