Relevance: Prelims
A team of Indian and French researchers have concluded that the hot arid desert of Kutch was once a humid sub-tropical forest with a variety of birds, freshwater fish and possibly giraffes and rhinos.
About:
- Their conclusions are based on the discovery of a tranche of vertebrate fossils from nearly 14 million years ago in a geological period known as the Miocene.
- The fossils, consisting mostly of ribs, and parts of teeth and bones, were unearthed from Palasava village of Rapar taluk in Kutch, Gujarat.
- Overall, the fossil finds from Palasava suggest that a rich diversity of fauna and flora sustained in warm, humid/wet, tropical to sub-tropical environmental conditions during the Middle Miocene (about 14 Mya).
- Geological changes eventually closed off the salt-flats’ connection to the sea and the region turned into a large lake, eventually becoming salty wetlands.
Significance:
- The findings showed Kutch to be a potential treasure trove of mammal fossils with possible continuity to vertebrate fossils in the Siwalik, spanning Pakistan to Nepal.
- The findings point to clues on how mammals dispersed between Africa and the Indian subcontinent when part of India was in the Gondwanaland supercontinent that existed nearly 300 million years ago.
Fossils:
Fossils are traces of ancient life. For many people the word “fossil” probably conjures an image of a bit of hardened bone or shell, but fossils can take many forms. An imprint of a leaf, an insect preserved in amber or a footprint are all examples of different types of fossils. Scientists use fossils to gather information about the lives and evolutionary relationships of organisms, for understanding geological change and even for locating fossil fuel reserves.
Dating Layers of the Earth
Fossils aren’t used only to understand individual organisms. Geologists also use fossils for what’s called biostratigraphic correlation, which allows researchers to match layers of rock in different locations by age based on how similar the fossils in each rock layer are. This information can be used to help understand when different layers of rock were formed even when large distances separate them.
Fossils and Oil
Fossils also have practical and commercial applications. The oil used in our energy and plastics industries tends to collect in specific types of rock layers. Because fossils can be used to understand the age of different rock layers as described above, studying the fossils that surface when digging oil wells can help workers locate oil and gas reserves.
And of course, coal, oil and gas are themselves called “fossil fuels” because they’re formed from the organic remains of prehistoric organisms.
Evolution
Perhaps one of the most important functions of fossils from a scientific perspective is that they constitute one line of evidence for understanding evolution. Using information pieced together from fossil evidence, scientists can reconstruct body types of animals that no longer exist and put together a “Tree of Life” to describe the evolutionary relationships between organisms.
The Fossil Record
Fossilization is a relatively rare process. Most organisms are not preserved in the fossil record. Because soft-bodied organisms, for example, usually don’t form fossils, there can be “gaps” in the fossil record.
Many exceptional deposits of fossils nevertheless provide a surprisingly detailed glimpse into the past and allow scientists to piece together a more complete picture of the history of life on Earth.