Pennsylvanian Period Facts That Give Insights Into History

Through this article, you're going to time travel your way to the Paleozoic Era and learn more about the Pennsylvanian Period.

The Carboniferous Period has been divided in North America as a geologic timescale of two epochs, the early, Mississippian, and the later, Pennsylvanian. During the late Carboniferous Period, Europe and North America were predominantly covered by tropical rainforests and present at the Equator.

Fossils obtained from the Pennsylvanian Period have been highlighting the existence of distinctive plants and animals that were buried in sediments due to orogenic land deformation, mountain-building, and similar other events that took place over the course of time. Trace fossils and impression fossils are the types of fossils that have been discovered.

The Carboniferous Period lasted from 360-300 million years ago; this was when swampy and dense forests came into existence that led to the creation of large deposits of peat. These deposits, then, as time went on, transformed into coal beds scattered across Western Europe and North America.

The swampy forests covered the continents, dead plant material accumulated, and pressure webbed compressed carbon, leaving coal behind. This is why certain areas have also been named 'coal forests'. The time that then came was of active mountain-building as Pangea came together, forming the Appalachian belt of eastern North America.

Timeline Of Pennsylvanian Period

The Pennsylvanian Period is renowned, although the exact date of the initial stage and final stage is quite undetermined by a difference of a few million years. Eastern North America's Carboniferous rocks mainly consist of repeated sequences of limestone, sandstone, shale, and coal beds.

The Mississippian Period's evidence is largely marine limestone; the Pennsylvanian Period has been characterized by deposition of coal beds.

Since the Carboniferous Period, North America has shifted today, being located as far north, no longer sitting at the Equator as it did about 300 million years ago.

The Mississippian Epoch climate was characterized by warm tropical humidity and high sea level, where sea life thrived. This continued for approximately 41 million years.

The Pennsylvanian Epoch was much drier, and the receding seeds gave way to the well-known coal swamps. The water was frozen into ice at the South Pole, creating a cooler climate worldwide.

With more land available, large rainforests grew, increasing the levels of oxygen in the air to around 35%, the highest the Earth has ever experienced.

The low levels of atmospheric carbon dioxide at the end of the Carboniferous Period are attributed to the drawdown and burying of carbon, creating today's immense coal deposits and setting off glaciation which continued well into the Permian Period.

Animals During The Pennsylvanian Period

The Carboniferous Period did not have the same large mammals that we see today. Instead, it was populated by a vast number of insects. Land animals were mainly composed of millipedes, snails, several insects, and more than 800 species of cockroaches.

The Pennsylvanian Period is perceived as a time of significant advance and retreat of shallow seas. The water was inhabited by fish, clams, mollusks, and sea urchins.

One of the particularly interesting fossils from this period is the Arthropleura. A giant millipede-like arthropod that would have dominated the land. These giant creatures thrived in the Carboniferous Period due to the high levels of oxygen that were in the atmosphere.

This plentiful oxygen filled the growth of such large arthropods. Please note that 'giant' here means that they were several meters long. Can you imagine a millipede that big?

Studies have claimed that the first reptiles evolved during the Pennsylvanian Period. These reptiles were about 1 ft (30.5 cm) long and were outnumbered by amphibians. Amphibians (vertebrates) were common and diverse in nature but were terrifyingly long as adults.

Plants During The Pennsylvanian Period

Throughout the Carboniferous Period, many spectacular plants dominated the terrain, thriving in the warm, humid climate, and swampy conditions. They were predominantly large trees covered in thick bark along with large ferns.

The coal-bearing rocks found in Ohio are proof of altering environments and escalation of both terrestrial life and marine life. Many plant fossils have been recovered from this era.

As time went on, the forests had been shifting further away from the swampy areas and were beginning to diversify. The boxwood ratio on trees increased as trees accumulated a molecule called lignin. The bark was so thick that hardly any organism could digest it.

Trunks, leaves, roots, and reproductive structures were ordinary in many shale beds, and their altered remains have led to the creation of coal beds that are of significance to Ohio. In Ohio, the Pennsylvanian System is characterized by beds of economically significant bituminous coal, out of which, some are expansive and thick, while others are the opposite.

Carboniferous Period's pteridophytes were centered around the waterlogged domains that developed inland. By the late Carboniferous Period, they had become the most common flora in their ecosystems. Scale trees such as the sigillaria and lepidodendron grew taller than 100 ft (30.48 m).

The final stage of the Pennsylvanian Period was marked by the progressive vanishing of huge coastal coal swamps, changes in animals and plants, and a dry climate.

FAQs

What animals lived in the Pennsylvanian Period?

Common Pennsylvanian marine fossils that were found gave the proof of existence for certain extinct animals; these included corals (Cnidaria), trilobites, clams (pelecypods), brachiopods, snails (gastropods), microscopic animals like conodonts, ostracodes, and squid-shaped animals like crinoids (Echinodermata), and cephalopods. Many reptiles, vertebrates, and amphibians also existed during this period.

What was life like during the Pennsylvanian Period?

Plants thrived in the coastal swamps located near the Equator, and varieties of horsetail rushes, conifers, ferns, lycopods (scale trees), and many others dominated the land. Marine life also flourished with aquatic species like fish, clams, mollusks, and sea urchins.

What went extinct in the Pennsylvanian Period?

The lepospondylians went extinct during the Pennsylvanian Period.

What time period number was the Pennsylvanian Period?

The Pennsylvanian Period was the second epoch of the Carboniferous Period. It lasted roughly from 323.2-298.9 million years ago.

How old is the Pennsylvanian Period?

The Pennsylvanian Period is more than 300 million years old.

What major events happened during the Pennsylvanian time period?

One of the major events that happened during this period was that most of the world's coal measures found today are a product of the processes that started back when the thick beds comprising dead plants were laid down by widespread swamps.

Which two important orogenic events began during the Pennsylvanian Period?

Linear deformation and mountain building were the two orogenic major events that occurred during the Pennsylvanian Period.

Why were insects able to obtain such large body sizes during the Pennsylvanian Period?

Due to tremendous amounts of oxygen in the air, insects and mammals were able to obtain such large body sizes during the Pennsylvanian Period.

When did the vertebrates appear in the Pennsylvanian Period?

The vertebrates appeared during the end of the Pennsylvanian Period, and the first to appear were lizards.