22
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Is there a geological explanation for the recent Mammoth tusk discovery 185 miles off the California coast?
The mammoth probably died on land.
Its remains got picked up by a glacier.
The glacier carried the tusk down to the sea.
Eventually, the ice containing the tusk broke off as an iceberg.
The iceberg ...
- 3,548
20
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Why are many fossils found in deserts?
Bones don't last very long in jungles. Or in forests. Or almost anywhere.
Fossils are the consequence of one highly unlikely fluke after another. Darwin himself commented on this. It takes just-right ...
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15
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Why are many fossils found in deserts?
Because you find fossils by looking at exposed bedrock, deserts by their nature often have huge expanses of exposed bedrock. The lack of plants is also a big benefit, plant roots tend to destroy ...
- 6,878
15
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What kind of rock is this being eaten by a rock-eating worm?
thank you for your interest in the article. I'm the lead author on this paper (Shipway) and I happened to come across your post when looking through all the media stories on this animal.
To answer ...
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12
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How do scientists measure the age of old animal remains?
Organic material (plants and animals) contains carbon.
Carbon has three main isotopes: carbon 12, 13 and 14. Carbon 14 is radioactive, with a half life of 5730 years.
Carbon 14 is continuously ...
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12
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Why were the early lifeforms of Proterozoic formation of India devoid of hard parts?
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 ...
- 3,548
10
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Why are many fossils found in deserts?
I would contend that the fact that the location is a desert has little to nothing to do in most cases to the existence of fossils at the location. Most of the fossils in the location, at least the ...
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9
votes
Connection between microbes and serpentinite?
The most common explanation for microbial activity in serpentinites is the exploitation of abiogentic hydrogen and methane formed during the serpentinisation process.
Quoting the abstract of a recent ...
- 23.1k
9
votes
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What is the oldest fossil on Earth?
The oldest undisputed fossil are Stromatolites, bacterial mats, the oldest of which are dated ay 3.7 billion years ago. The key term here is undisputed, there are other possible fossils but it is very ...
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9
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Has there ever been a case where we have found what appears to be a prehistoric fossil but have no way of dating it?
The short answer is no, because we always have some constraint of how old something is. Sometimes we have fossils with large date error bars, and often we do not know for how long that species ...
- 1,035
9
votes
What is this fossil found in flint in Kent?
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 ...
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8
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What is Oligo-Miocene radiation?
The ‘Oligo-Miocene’ part
The Oligocene and the Miocene are epochs of geological time. The Oligocene lasted from ~33.9 million years ago to ~23 million years ago; the Miocene followed immediately ...
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8
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What is this fossil? What is this crystal?
Yes, this is a rather nice find; an ammonite of the Jurassic in central Europe. Given the size of the specimen, and its appearance, this appears to be of the species Cardioceras, or Perisphinctes. ...
- 96
7
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Do you have any informations about fossil-rich cherts from Scandinavia?
What you are looking for is information about the "Oslofeltet" (Oslo-field) in Norway (dated to be from the Ordovicium period, 443 - 488 million years old). This is a concentrated field of of fossils. ...
- 1,868
7
votes
Dino-birds or "Pigeon-o-saurus"
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 ...
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7
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Book on the history of Earth and life on Earth
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 ...
- 6,878
7
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Why aren't diatoms' shells used as a temperature proxy, but foraminifera shells are?
Lacustrine diatoms are used extensively as reliable conventional proxies in Holocene (within the last 10,000 years) paleoclimate studies. According to this 2010 paper:
(paleoclimate) Reconstructions ...
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6
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Aligator or Dinosaur Fossil skin type rock
I agree with commentator @John, this is a fossil coral. The coral animal (the polyp) builds a column, and as it ages it closes off the bottom and extends the upper lip. In some of the views you see ...
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6
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I have found this fossil tooth, could it be pliosaur ? Or maybe theropod?
Most likely plesiosaur. That fluted structure is indicative of marine reptile teeth. My first guess was mosasaur but their are a lot of plesiosaurs from that formation so I would go with that. It is ...
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6
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What are 'articulate shells'?
If I remember correctly from my intro to paleo class, the terms articulate and inarticulate refer to a classification of brachiopods depending on the nature of their hinge. Articulate brachiopods have ...
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5
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How old are Pecten fossils in general?
Pectens seem to have evolved from Chlamys in the late Eocene or early Oligocene. The coarseness and rib spacing of Vertipectens has been slowly evolving since the early and Mid-Miocene, so they have ...
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5
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Are Pompeii and Herculaneum unique?
Probably the best known is more recent, the 1902 eruption of Mt. Pelée on Martinique, where 30,000 people were killed by pyroclastic flows. I don't know the extent of burial - it appears that the city ...
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5
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What type of mammal does this fossil tooth belong to?
It's an entelodont, South Dakota is famous for it's Oligocene mammalian faunas which include entelodonts such as Archaeotherium and Daeodon.
here is an http://i.ebayimg.com/images/i/181202162847-0-1/...
- 1,339
5
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Fossil from North Norfolk coast, UK
The round one is a belemnite... The grid-shaped fossil is a bryozoan. Bryozoans were (and are) marine colony building organisms often encrusting shells and other hardgrounds in the oceans. There are ...
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5
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Has there ever been a case where we have found what appears to be a prehistoric fossil but have no way of dating it?
Yes it does happen, and we know when and why it happens.
Bad collection. The most common reason is because of bad collection methods. Some times laypeople collect fossils without recording where or ...
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Is this a fossil?
Yes it could be a fossil. Btw. it is called a sand dollar.
The term sand dollar refers to several species of flattened burrowing sea urchins that belong to the order Clypeasteroidea. Sand dollars, ...
- 1,910
4
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Why are many fossils found in deserts?
Because there is nothing in the way. Looking for stuff in a jungle is difficult because of limitation of vision and difficulty of moving equipment and supplies.
Looking for fossils in downtown ...
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4
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What is the age of the earliest traces of life on Earth?
The oldest (fairly) definitive fossils date from about 3.48 billion years ago (Ga) and consist of sedimentary structures associated with microbial mats living in coastal environments.[1]
Beyond this ...
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