11

Fishing through the links mentioned over at Christianity SE, I netted this scientific paper about freshwater and marine fish: Why are there so few fish in the sea?. Apparently the bulk (96%) of marine species have a single freshwater ancestor species extant 300 Mya (300 million years ago). Descendants of this species did not enter the ocean until about 180 ...


10

Rings wouldn't decrease the gravity much, but the exact amount would depend on the exact geometry of the rings. One reason is that the gravity of one side of the ring would partially cancel the attraction of the other side. In a similar fashion described by the Shell theorem demonstrated long ago by Newton and proving that if you are inside a shell of mass ...


8

There are definitely many examples of overlying Mesozoic strata that contain characteristic dinosaur fossils (and ichnofossils – i.e. trace fossils). One of the best examples is the Mesozoic stratigraphy of Utah and Colorado. However, most geologic intervals are characterised by less ‘famous’ fossil material (e.g. molluscs, trilobites or pollen grains). This ...


8

If U-shaped in cross-section, it is plausible that these are the partial remnants of lava tubes. See, for example, Morphology and mechanism of eruption of postglacial shield volcanoes in Iceland (Rossi, 1996). It is difficult to propose more detailed formation mechanisms in the absence of significantly more information about the structure.


7

First, let me link a variety of popular science articles which can give you some background explanation. Here are Scientific American, Smithsonian, and Audubon magazines. The 'smoking gun' evidence linking birds and dinosaurs is the evolution of feathers. Feathers are a feature that set the birds apart morphologically from the rest of the tetrapods, and ...


5

I'm not going to give an extensive account on "mass extinction" epistomology here but I think the first thing one has to consider is the difficulty of studying numerically paleobiodiversity (mostly because of a gappy fossil record but also an historically unbalanced sampling effort and the rock availability for some of the time periods); although, along the ...


5

No. The reason for Australia’s unique evolution is that it was relatively isolated from the rest of the world. Australia isn’t too radioactive either. The fact that it has more uranium deposits than other countries is that it’s huge.


4

The geological, hydrological, meteorological, palaeontological, evolutionary and hydrodynamic absurdities of the literal reading of Noah's Flood could fill at least one lengthy book, in fact many such books, and are way too numerous to do justice in a short Stack Exchange article. The short answer is NO, one cannot even begin to explain the discrepancies ...


4

Forty years ago, protein electrophoresis and other molecular types of dating were pointing to a date of 4.5 million years BP for the separation of the hominid line from the pongid (great ape) line, but I didn't believe it at the time because it conflicted with the fossil evidence. Since then, more fossils have been found and the disparity between geological ...


3

A weed is just a plant where you do not want it. Totally a matter of context. Tumbleweeds are non-native, introduced centuries ago. I assume you mean the invasive species of plants that have been spread by humans and are disrupting ecologies throughout most of the world Until recently, these plants we consider weeds were limited in their range to home ...


3

The vast majority of magma never even makes it out to the surface - most is simply crystallised at depth in magma chambers which dead-end several kilometres below the surface, or are injected as dykes or sills within the host strata. By OrbitalPete, posted on reddit.com If magma rose up below that mound it probably got closer than several kilometres to the ...


3

(tl, dr at the end, the answer by user user18411 is mine from a former life on this site) Addressing @MichaelWalsby's answer that contains numerous false claims and severe misunderstandings and lacks citing: Forty years ago, protein electrophoresis and other molecular types of dating were pointing to a date of 4.5 million years for the separation of the ...


3

Ahhhh, probably not. If, for example, you navigate to Marsupial at Wikipedia and click on the wonderful (it really really is!) DyMaxion map at the bottom of the info panel, you wiil see that a large part of South America, Central and North America also have these animals. FWIW, the USA does indeed have Uranium deposits although I'm not sure about Central ...


2

The jaguar is a close relative of the Asiatic leopard and must have had a common ancestor within the last 5 million years. The South American tapir is obviously closely related to the Malayan tapir and must also have had a common ancestor within he last 5 million years. While the first statement is more or less correct, the latter is not. The Asian and ...


2

At the northern and southern ends of the Sea of Japan, there are only short stretches of very shallow sea separating Japan from the mainland. During the Ice Age which ended 12,000 years ago, sea levels were much lower than they are today. It is probable that during the last Ice Age there were land bridges connecting Japan to the mainland at these two points.


2

This very much looks like a lava tumulus to me. Tumuli are a very common feature in pahoehoe lava flow fields. There is a classic paper by Walker (1991) describing their morphological characteristics and formation process. They are formed by inflation of the cold, stationary crust which is lifted upwards by the influx of new lava underneath. From what I see ...


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