Animal and plant fossils develop when upon death they are rather quickly covered in water or sediment or sand which helps prevent them from becoming prey to scavengers or rot. Even volcanic ash from an eruption can be the blanketing medium. Flesh is often stripped from the bones of animals by bacterial action before fossilization. Sometimes tree sap traps small animals like insects and preserves them in amber rock. Sea animals with hard shells leave imprints of these parts preserved in stone, or the hard parts may be replaced with minerals such as calcite, quartz, or pyrite. Mineral replacement fossilization can take an amazingly short period of time, on the order of decades in some instances.
Fossils can be used as evidence for evolution because they can show the development of a species over a long period of time.
The study of fossils represent the evolution of species by the time period between when they became fossils and what the ancestory line is
today's species evolved from those of the past.
Index fossils (also known as guide fossils, indicator fossils or zone fossils) are fossils used to define and identify geologic periods (or faunal stages). They work on the premise that, although different sediments may look different depending on the conditions under which they were laid down, they may include the remains of the same species of fossil. If the species concerned were short-lived (in geological terms, lasting a few hundred thousand years), then it is certain that the sediments in question were deposited within that narrow time period. The shorter the lifespan of a species, the more precisely different sediments can be correlated, and so rapidly evolving types of fossils are particularly valuable. The best index fossils are common, easy-to-identify at species level, and have a broad distribution-otherwise the likelihood of finding and recognizing one in the two sediments is minor. --- Wikipedia
Index
Fossils are used to show changes because they are permanent. These fossils are also old and show evolutionary changes in species alive today.
Fossils can be used as evidence for evolution because they can show the development of a species over a long period of time.
Fossils show that there have been many different species of organisms that have lived on Earth throughout its history. These fossils provide important clues about the evolution and biodiversity of life on our planet.
Fossils show clear evidence that the earliest human species had many apelike features & have evolved over the years.
Fossils are evidence of biological evolution because they provide a record of past life forms, showing the progression of species over time. By studying fossils, scientists can trace the development and diversity of organisms, providing insight into how species have evolved and adapted to changing environments.
Fossils show certain species underwent small changes over a period of years the rock in which the fossil is encased dates the fossil and so they can put them in order to show the progression of the physical changes
If there was no change in species over time, then all fossils of that species would be identical.
Actually yes it can. Embryos, DNA sequences, and fossils amongst others things can help show similarities within species. This can show that those species have similar traits because they evolved from a common ancestor. But those differences show why they are different species and thus evolving.
Fossils' existence confirms that species are not fixed but can evolve into other species over time
Geologists use fossils to interpret past environments, age rock layers, and understand the history of life on Earth. Fossils can provide information about the evolution of species, past climate conditions, and even the movement of continents over time. By studying fossils, geologists can reconstruct the Earth's history and better understand geological processes.
The fossil evidence is spectacular, demonstrating evolution. Hundreds of specimens of mammal-like reptile fossils have been found. The fossils, gradually and (hypothesised from fossils) phylogenetically, show the development of the mammalian jaw both osteologically and dentally.Fossils show the transition of sarcopterygian fish around the Devonian from fish to terrestrial amphibians like Icthyostega and Acanthostega.Fossils show, gradually across time, from oldest to most recent, the development of the Equus hoof, the decrease in the number of toes of such an animal, from Eohippus to Equus.Many species of feathered dinosaur have been found, such as Sinosauropteryx and others and this lends much support to the theory that birds evolved from a group of dinosaurs.Across time, the development of the titanothere horn can be seen through fossils from the Eocene to the Oligocene (Ridley M., 2004, Evolution)The development of humans can be seen across time, through the Australopithecus and Homo genera.
"Scientist have combined the evidence of DNA, protein structure, fossils, early development, and body structure to determind the evoltionary relationships among species."