Fossils of embryos
The embryo fossils have been found dating back more than 500 million years ago. These fossils have been found in China and Siberia. They are preserved in the rocks. Using intense x-rays generated by particle accelerators, scientists now can peer into the fossils. The structure of the embryos have been found by synchrotron x-ray tomography microscopy. Scientists of the University of Bristol have found the fossil to be of Markeulia, a worm like animal. The scientists have found the gut of the embryo when they observed a hollow space. With a closer view, the scientists found that the hollow are the result of the incomplete fossilization, not the structure of the embryo. Embryo is an early stage of development of an organism in the egg or the uterus, during which its essential form and its organs and tissues develop
Fossil is the remnant, impression, or trace of an animal or plant of a past geologic age that has been preserved in the earth's crust.
The data recorded in fossils, known as the fossil record, constitute the primary source of information about the history of life on the Earth. Only a small fraction of ancient organisms are preserved as fossils, and usually only organisms that have a solid skeleton or shell. A shell or bone that is buried quickly after deposition may retain organic tissue, though it becomes petrified (converted to a stony substance) over time. Unaltered hard parts, such as the shells of clams, are relatively common in sedimentary rocks. The soft parts of animals or plants are rarely preserved. The embedding of insects in amber and the preservation of mammoths in ice are rare but striking examples of the fossil preservation of soft tissues. Traces of organisms may also occur as tracks, trails, or even borings.
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