--- title: Fossils: how we know about life long ago — a lesson of Mova's school · trees and pragmatics description: «Fossils: how we know about life long ago», a lesson of the biology course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: A fossil is a message from a world nobody saw: the remains or traces of a living thing kept in rock, ice or amber for thousands o --- [Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/) [home](https://md.mova.elamur.ai/free/en/) / [corpora](https://md.mova.elamur.ai/free/en/corpora/) / [school](https://md.mova.elamur.ai/free/en/corpora/school/) / [Biology](https://md.mova.elamur.ai/free/en/corpora/school/biology/) / Fossils: how we know about life long ago # Fossils: how we know about life long ago Lesson 74 of the biology course of Mova's primary school: 15 sentences, each with its syntax tree and pragmatics. The lessons are written for Mova, and their agreed trees are part of Mova corpus 0.4 (CC BY-SA 4.0). How Mova does on its tests: [the lesson at school](https://md.mova.elamur.ai/free/en/school-run/biology/74-fossils-life-long-ago/). - [0](https://md.mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/0/) — A fossil is a message from a world nobody saw: the remains or traces of a living thing kept in rock, ice or amber for thousands or millions of years. - [1](https://md.mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/1/) — Most fossils form when an animal is buried fast in mud; over ages the mud becomes rock and minerals slowly replace the bone or shell, leaving a stone copy like the spiral ammonite you might find on the beach at Lyme Regis. - [2](https://md.mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/2/) — Fossils are not only bones: footprints, burrows, tooth marks and even fossil poo tell scientists how animals walked, what they ate and who bit whom. - [3](https://md.mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/3/) — In films dinosaurs are cloned from blood in amber mosquitoes, and in cartoons cavemen ride dinosaurs; real fossils say no to both, because DNA breaks down far too fast and tens of millions of years separate dinosaurs from people. - [4](https://md.mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/4/) — Ammonites were sea animals with coiled shells, related to octopuses and squid, that died out with the dinosaurs about 66 million years ago; fossil hunters keep away from cliff bottoms, where rocks fall, and check the tide times. - [6](https://md.mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/6/) — Most fossils form when a living thing is buried quickly, and minerals carried by water fill or replace the remains; only a tiny fraction of living things ever become fossils, because most remains are scattered, eaten or rot first, and soft animals like jellyfish, with no hard parts, almost never do. - [7](https://md.mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/7/) — Trace fossils such as footprints, burrows, nests and tooth marks are signs of life, and the distance between steps tells how fast a dinosaur walked. - [8](https://md.mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/8/) — Amber is fossilised tree resin that can trap small insects; dinosaurs cannot be cloned from amber insects because DNA breaks down far too fast to last 66 million years. - [9](https://md.mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/9/) — Rock layers are laid one on top of another, so lower layers are usually older; scientists date volcanic ash layers with natural atomic clocks in the rock. - [10](https://md.mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/10/) — Megalodon was a huge shark from about 23 to 3.6 million years ago with teeth up to about 18 centimetres; its skeleton was cartilage, which rarely fossilises, so mostly teeth remain. - [11](https://md.mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/11/) — Coprolites are fossilised droppings that show what ancient animals ate; William Buckland recognised them in the 1820s, and Mary Anning noticed them inside ichthyosaur skeletons. - [12](https://md.mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/12/) — Lyuba, a baby woolly mammoth about 42,000 years old, was found in 2007 in frozen Russian ground with her skin and trunk; mammoths survived on Wrangel Island until about 4,000 years ago, after the Egyptian pyramids were built about 4,500 years ago. - [13](https://md.mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/13/) — Archaeopteryx lived about 150 million years ago in what is now Germany, with feathers and wings like a bird but teeth, claws and a bony tail; it was found in 1861. - [14](https://md.mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/14/) — Rocks near the top of Mount Everest hold fossils of sea creatures, because India pushing into Asia lifted an old sea floor into the Himalayas, which still rise a few millimetres a year. - [15](https://md.mova.elamur.ai/free/en/corpora/school/biology/74-fossils-life-long-ago/15/) — Sue, one of the largest and most complete T. rex skeletons with about 90 percent of the bones, was found in South Dakota in 1990 by Sue Hendrickson and stands in the Field Museum in Chicago; the skeleton is named after its finder, and nobody knows if Sue was female or male. - ← previous: [Evolution simply: why living things change over many generations](https://md.mova.elamur.ai/free/en/corpora/school/biology/73-evolution-simply/) - next →: [Dinosaurs: kinds, sizes and how they lived](https://md.mova.elamur.ai/free/en/corpora/school/biology/75-dinosaurs-kinds-sizes-and-lives/) - ↑ back to [Biology](https://md.mova.elamur.ai/free/en/corpora/school/biology/)