Prehistoric Pakistan Few things capture our collective imagination like the past. The further back in time, the greater the sense of mystery. For many, their first taste of pre-history came during childhood. It may have been a movie or documentary, or something as simple as an illustrated book. But that very first instance had most of us hooked. Re-imaginations of prehistory provided us the closest glimpses we had of what an alien world might look like.
About 200 million years ago, a giant landmass known as Pangaea began to break up through tectonic plate movement caused by mantle convection. The supercontinent thus began to separate due to the new material and thus continents began to form. Similarly, as land kept dividing over the years, animals also kept dividing with the land. Few became extinct with the changing environmental conditions while few were preserved in history in the forms of fossils. Over the years, millions of fossils have been discovered which are the remains or impressions of prehistoric plants or animals embedded in rocks and are preserved in petrified forms naturally.
Researchers, working on these have discovered many things over the years. The biggest and easiest understanding to what paleontologist does is dinosaurs which existed in the world millions of years ago and today we have discovered many species and different characteristics of them. The studies have helped establish a wealth of information on what the world may have looked like millions of years ago.
To further understand this, the eras of studies have been divided into Cambrian, pre-Cambrian, and Pleistocene. Pre-Cambrian is the era that began nearly 4.6 billion years ago when the earth started to form while Cambrian is the era, which is 600 million years ago. Pleistocene’s fossils are the ones that are recent and date back to around 2.5 million years old. While nearly all life forms have originated in the Cambrian era, some earlier rocks do group into the pre-Cambrian times.
With scientists and researchers excavating lands across the world, some valuable treasures have been discovered buried beneath the land. The region we live in is no different. Pakistan’s land is very rich in terms of fossils. From a large number of invertebrates to some wild animals, Pakistan has been home to elephants, dinosaurs, rhinoceros as well as an infinite number of marine invertebrates.
Karchat wildlife sanctuary near Thatta is the hub of wild animal fossils. “Many impressions of life have been found here, be it children, elephant trunks and teeth or horse toes. There’s proof [in the form of fossils] that millions of years ago elephants used to live in Sindh whereas today as one cannot even think of elephants living in in this region,” said Professor Dr (retired) Gulraiz Hamid.
“No mammals have been found Karachi. The region was supposed to be underwater and it was all sea millions of years ago which is why mostly invertebrates are found here. We also have majorly exposed rocks, which are from the Pleistocene era,” said Dr Hamid who was a professor of Geology at the University of Karachi. Recently, some researchers have found two shells, named Pecten and are from the Miocene age. A few others which are found in the region are Gastropods and Oligocene.
The fossil which is specifically found in Karachi is called Phylum which is a brachiopod and an inarticulate which is called lingula and is still alive – all these are from the Cambrian era which dates back to 600-650 million years ago.
The weather and coastal conditions of the city have played a major part in preserving or making the fossils wash away but with favorable conditions, the oldest rocks are still found in Mauripur, in Kemari Town of Karachi. “The oldest rocks are there but the pre-Cambrian fossils are mostly extinct now because of the changing environmental conditions by the coast. The Lingula on the hand, which is a bat-shaped species, due to favorable conditions is still found alive and in fossils too,” said Dr Hamid. “Researchers found shells which are coral reeves and are Australian coral. These are mostly found in Manghopir and the hub river coastline. Other than that, the most common find is from Miocene, which is estimated to be 200 million years old,” the geologist added. The Pelesetope, which transforms into a pearl was found 10 to 15 years ago by a marine scientist. The discovered fossil was gleaming black pearl.
In tertiary rocks, many fossils which have been found from Oligocene and under it Phylum for mini sera are found. Microfossils are found in a greater quantity as organic remains are important however, most of the research in the discovery of these fossils in Karachi has been ceased due to a lack of interest from students in this field. A few years ago, small stones were found which contained preserved fossils of fish. A few of the discovered fish was complete with ribs and hearts. The discovery was said to have been from the tertiary era, which goes back about 200 to 300 million years ago. Sindh mostly comprises Paleocene fossils however, recently Cenozoic, which are also from tertiary rocks, was also found.
The most interesting fact about this is that most of these fossils are wasted as most people are unable to identify them. For example, the mountains in Karachi near North Nazimabad and Orangi Town are replete with microfossils, mostly with lepidocyclina which look like white chips. Myo-gypsina, assilina, alveolina, nummulites, obtusus, and eoscene time rocks all are found in great numbers, which have several invertebrates preserved in them. When light reflects on them either they shine or if look closely, one can find impressions of species within them.
To grasp just how unaware we are of the presence of fossils and how in the absence of that knowledge, we are continuing to damage them can be observed from the fact that obtusus is found near Shah Noorani Mazar near Baluchistan and the believers call them Hazrat Ali Pir’s Tabarruk (Consecrate) which is a red-colored fossil shaped like a rock. Visitors of the Mazar take these rocks back home with them and eat them as tabarruk while all these are fossils of pulses, just like nummulites, which look like black pulse.
After the 1970s, water began to move backward and the area near Abdullah Shah Ghazi shrine was been developed into a residential area but even there, ostrea can be found very easily which is pectin and as well as cypraea (which is used in jewelry), which is also a fossil shell.
Other than several findings in Karachi and its surroundings, corals are still alive on Gadani but are found in colonial forms as they also die in colonies and form like packs in the shape of honeycombs. All this is due to sea conditions, which are not very friendly for them. Phylum cnidarian is like skin and spine and is from said to be Oligocene or Miocene times and are famously known as clypeate and found in the shape of flower petal near hub river road. The region has been filled with many fossils and is rich in paleontology but the most famous ones found are lingula, coral, and gastropods.
According to the University of Karachi Geology department Professor Dr Aqil Farooqi, Pakistan mostly contains fossils that are linked to the sea or have been part of the sea and have marine fossils. Marine fossils mostly have similar characteristics and worldwide life but with rocks, the ages are less comparative to sea fossils. “Pakistan does not have many land fossils. The discoveries are few and very rare but it is not that nothing has been found yet. For example, the largest fossils which have ever been found in the region were found from the Potohar region which was of rhinoceros. The fossil, which was said to be around 60 million years old, was found in the British era between 1800 to1900,” he said.
The majority of the microfossils which are found in Sindh are from sedimentary years and if to describe them in specific geological years then the rocks formation which is exposed in Sindh are mostly from tertiary age, which are approximately 25-60 million years old. “Initially the tertiary period started 65 million years ago when human life started, that is since when these fossils are also exposed,” told Dr. Usmani.
The two plates, Planktonic Foraminifera are exposed in Ranikot area of Sindh which are the best indicators to confirm the geological age of the rocks and also help in searching oil and gas in the region. “There are prospects of oil in Sindh, and Planktonic is the proof that such formation was exposed here, similarly Benthonic Foraminifera are also found in vast number from Lakhra which have huge deposits of coal and also help to know the environmental conditions of deposition of rocks,” she told adding that the province has heavy coal deposits and it that terms such fossils have been part of several types of research, the land near Lakhra and for that say Thar as well is extremely sensitive from Mineral’s point of view.