12

Simply put, life hadn't evolved any 'hard parts' yet. This applies to the Proterozoic all over the world, not just in the part of Gondwana that became India. 'Hard parts' usually means tissue that is already mineralized. For example, (vertebrate) bones or (mollusk or brachiopod) shells are made of calcite or aragonite. This material is durable over ...


9

That is a sea urchin (echinoid) or at least part of one. the pattern of plates is fairly distinctive. 2 rows of small plates alternating with 2 rows of large plates. I am not familiar enough with urchin phylogeny to give you species but you might be able ot get it from the biology stack.


6

Cowen's History of Life Your best bet is Cowen's History of Life, it is an excellent introductory textbooks for paleontology well laid out and clearly written with introductory students in mind so a laymen will be fine. It covers the entire breadth of the life. Check the edition though there are six of them now and the older ones are pretty outdated and not ...


4

The approach adopted by Charles Lyell (and other writers in a similar timeframe), in his book 'Principles of Geology' which was first published in the 1830s was to look at processes in the modern landscape where the rate of change could be determined by observation or from historical evidence, and assuming that similar processes operated at similar rates in ...


3

The first coal deposits were laid during the Carboniferous period, between 358.9 million years ago and 298.9 million years ago. Within this period, the early Mississippian period from 358.9 to 346.7 Mya, was when the first coal deposits were being laid. During this period, coal was being laid in what is now eastern North America, specifically the Kentucky ...


3

Yes it does happen, and we know when and why it happens. The most common reason is because of bad collection methods. Some times laypeople collect fossils without recording where or when the collected it, in those cases the fossil has no providence and is generally useless for scientific analysis. As long as you know what rock formation a fossil comes from ...


2

Definitely an echinoid (sea urchin) and they are often found in the flints in the chalk cliffs along the south coast of the UK. Seaford in Sussex is particularly well known for these types of fossils.


1

To answer your question, "...surely there have been cases where we have found new fossils that we have no way of knowing the age?", the short answer is yes. Prior to modern radiometric dating in the early 1900s, which placed firm constraints on age, you could say that all fossils found until that point were of unknown age. Sure, you could establish ...


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