Scientists discovered 92 percent similarity of DNA from ostrich, Struthio camelus, of Africa to that of fossilized eggshell found in India. This supports the theory that ostriches once thrived in India as well. The catch is; these birds roam the area some 25,000 years ago.
Scientists have been thinking that ostrich existed in India thousands of years ago but the only proof that supports the theory is a study of morphological features. This approach can't present conclusive evidence and has been a subject of debates. However, recent studies used molecular evidence and DNA tests. This approach is more accurate than the former.
There are 11 fossilized eggshell samples gathered from 3 different sites in India. Scientists then isolated the DNA from 5 samples then created a sequence. Other shells were not used because they only present 30 base pairs, risking a faulty reconstruction of mitochondrial samples, according to science journal Plos One. The exposure of the samples to the hostile environment was also taken into consideration.
According to Dr. Kumaramsamy Thangaraj, it is challenging to amplify these DNA fragments since the eggshells were very old and not well-preserved. However, eggshells are known as the better sample than bones for DNA extraction primarily because of its intra-crystalline structure that minimizes contamination, according to The Hindu News.
The process proved painstakingly delicate but scientists managed to arrive at a tangible conclusion. It is by sheer luck that these eggshells didn't completely change its calcium carbonate composition into magnesium which could ruin the DNAs. The study also marked the first time when experts tried to extract preserved DNA from fossil eggshells in a tropical environment.
If ostriches were roaming freely on the land mass of India and Africa, what caused the separation and eventual seclusion of the African cousins? Experts believe that the Indian landmass drifted away from Africa in an event called the continental drift, making the two ostrich groups to be separated from each other. Eventually, people associated ostrich to Africa while their Indian counterparts were wiped out.