Land Mammal to Whale transition: fossils

Maybe give some thought to why fossilization is rare. Normally, when creatures die they are pulled apart and eaten by scavengers, not leaving much to be fossilized. For a fossil to form, specific conditions have to be in place. Some examples, an animal falls into a tar pit, or sinks in mud, or buried by a landslide. Things like this tend to be in a specific location at a specific time. What was mud at one time may be solid rock a couple of thousand years later. So, if there is a relatively narrow window of opportunity for a specific fossilization event, I don't see it as strange that certain species may be more likely to be fossilized. Particular habitats and habits could easily put some creatures further 'in harms way' from a fossilization perspective that many other creatures.Food for thought?

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On the 7th day, God was arrested.

Sometimes yes, but not necessarily always. To expand a little on my previous post, a creature may inhabit a very wide area but might like a specific type of habitat, which may expose it to greater likelihood of fossilization wherever in the world it may be. For example, say a particular species has a fondness for hanging around mudflats or muddy riverbanks to feed on crabs or worms or whatever else may like to live around there. Therefore, it’s spending much of its time in conditions where there is a greater chance of being fossilized by sinking in soft mud. Soft mud is likely to be found in more than one specific place, so if it behaves like this throughout its entire range then it’s possible you may find multiple fossils in various locations. Continents were not always a barrier. Continents that are separate now were once joined, and some that are one now were once separate. There doesn’t even need to be much of a link, a relatively narrow land bridge is enough, as animals are mobile and may move from place to place. Climatic changes or lack of food in one place could arise in a relatively short time, so animals will migrate to more favourable conditions. The land bridge breaks, and then these animals find that they are now on a separate continent. As for the following species not being found, I’ll again use my hypothetical mud-loving animal to speculate. Say there is a climate change and the mud eventually dries up, animals start dying, so those remaining are forced to move away to find food elsewhere. Some of these animals adapt to living in the jungle. Another group adapt to living in grasslands. As they’re different environments, each of these groups would evolve slightly different features. However, these new environments do not easily allow for formation of fossils. So humans come along several million years later and find a bunch of fossils of the mud-lovers but none of their descendant species that moved to new habitats.I know this is not a ‘real’ example, but it is not meant to be. It is rather a speculation on a logical way that the situation you described could occur. And that is what we need to do sometimes, to look beyond what may be obvious in front of our faces, and think outside the square.On top of all this, it is important to note that we humans can only dig up so much of the earth’s surface because, to put it simply, it’s rather big. Furthermore, of it is at the bottom of the ocean, where it isn’t easy to go digging for bones. It is not reasonable to assume that we have found all the fossils that are lying in the earth’s crust. It is possible that we humans have only seen (or indeed will ever see) the tip of the iceberg of the creatures that have lived here.

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On the 7th day, God was arrested.

Habitat meaning water in general, yes, but water has different habitats within. Different parts of the world have different water temperature at different times of the year. Different food is found in different places, predators, etc. If the mud were very soft, could it not sink and be unable to get out? Sort of a quicksand like thing. Whales may float, but some whale ancestors might not do it so well. Anyway, I wasn’t specifically thinking whales there, just trying to illustrate the general concept. Mud happened to be the first thing I thought of for an example. I don’t see why that should be the case. Whales are not just found in one part of the ocean, they migrate, which gives them some range. It’s also well known that some whales beach themselves. Possibly certain whale ancestors had this trait and formed some fossils as a result, while other species living at the time were not quite so fond of going to the beach. Doesn’t sound impossible. I don’t think it’s reasonable to say that this indicates the species are not there, or for that matter, if they are there. All it indicates is that we have not seen them. Refer to the last paragraph in my last post, the basic point is that I’m certain there are a lot of fossils that we have not found, many of which we may never find.I would also like to make mention of Basilosaurus. This is a whale that actually had two small hind legs, that were too small for movement in the water. It is hypothesised that they may have been used to help with mating. IMHO I think it’s reasonable to say that a whale with small hind legs suggests it evolved from something with legs, which are an adaption for movement on land and not of much use in the water.

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On the 7th day, God was arrested.