A fossil from Classical Latin : fossilis , literally "obtained by digging"  is any preserved remains, impression, or trace of any once- living thing from a past geological age. Examples include bones , shells , exoskeletons , stone imprints of animals or microbes , objects preserved in amber , hair , petrified wood , oil , coal , and DNA remnants. The totality of fossils is known as the fossil record. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance.
Scientists Find Soft Tissue in 75-Million-Year-Old Dinosaur Bones
How Do Scientists Determine the Age of Dinosaur Bones? | HowStuffWorks
Dinosaur , clade Dinosauria , the common name given to a group of reptiles , often very large, that first appeared roughly million years ago near the beginning of the Middle Triassic Epoch and thrived worldwide for nearly million years. Most died out by the end of the Cretaceous Period , about 66 million years ago, but many lines of evidence now show that one lineage evolved into birds about million years ago. Dinosaurs are a diverse group of reptiles that were the dominant terrestrial life form on Earth during the Mesozoic Era , about million years ago. Dinosaurs went into decline near the end of the Cretaceous Period , about 66 million years ago. The decline of dinosaurs was most likely caused by many different factors. This would have severely impacted plant life and subsequently brought about the end of most dinosaurs.
How we date dinosaur bones
A new and gigantic dinosaur which could rival the largest known species is being unearthed in Argentina. However, the remains are not a complete skeleton, and consist mainly of pelvic bones and vertebrae, only giving an indication of the enormous scale of the animal. The authors of a paper presenting the research on the find published in the journal Cretaceous Research suggest the animal could come from a previously unknown population of Patagonian sauropods. These large sauropods grew to be 18 metres long. However, the fossilised bone fragments indicate the new titanosaur was far larger, easily exceeding Andesaurus in size and likely making it bigger then the largest known land animals, the Patagotitan and Argentinosaurus - both types of sauropods.
A new species of titanosaur unearthed in Argentina is the largest animal ever to walk the Earth, palaeontologists say. Fossilised bones of a dinosaur believed to be the largest creature ever to walk the Earth have been unearthed in Argentina, palaeontologists say. Weighing in at 77 tonnes, it was as heavy as 14 African elephants, and seven tonnes heavier than the previous record holder, Argentinosaurus.