The Cenozoic Era is divided into several periods and, in turn, into several epochs. Today we're going to talk about the second period of this era: the Neogene . It began about 23 million years ago and ended 2.6 million years ago. It's a period in which the planet underwent a series of changes and transformations, both geologically and in terms of biodiversity. One of the most significant events of this important period is the appearance of Australopithecus, one of the main ancestral species of Homo sapiens.
In this article we are going to tell you everything you need to know about the Neogene and its importance in geology.
Key features
The Neogene period was a time of intense geological activity on our planet, both in terms of continental drift and sea level rise. The continents continued their movement to their current positions due to plate tectonics, driven by convection currents in the Earth's mantle.
Due to this movement of continental plates, marine activity also changed. Ocean currents were altered as physical barriers emerged and wind patterns changed due to climate change. This event was quite significant as it had an immediate impact on Atlantic Ocean temperatures. One of the most important physical barriers that arose as a result of this plate movement was the Isthmus of Panama. Furthermore, during this period, the geological features that led to the formation of the Betic System can be observed , which is relevant to understanding Neogene geology.
During this period, biodiversity also developed extensively. Terrestrial mammal groups underwent the most significant transformation. Birds, reptiles, and marine life also experienced considerable evolutionary success, reflecting the richness of Neogene fauna.
Neogene Geology
As we have mentioned before, this is a period where there is high geological activity from the orogenic point of view and from the point of view of continental drift. The fragmentation of Pangea continued and the various fragments that originated began to form a displacement in different directions.
During this period, several landmasses collided with southern Eurasia. These landmasses were North Africa and what is now India. India did not drift on its own but rather pressed against Eurasia. This is how the continental masses were uplifted, forming the mountain range we know today as the Himalayas.
The formation of the Isthmus of Panama had immediate consequences, causing a considerable variation in global temperatures. More specifically, it affected the temperatures of the Pacific and Atlantic Oceans, leading to a decrease in their intensity. Within this geological context, we can understand how climate influenced the development of various ecosystems, as described in our entry on ice ages.
Climate
Regarding climate, throughout this period, our planet was characterized primarily by a global decrease in temperatures. In particular, territories located in the Northern Hemisphere experienced a slightly warmer climate than those in the Southern Hemisphere. Similarly, the climate changed over time, as did existing ecosystems. These changes in ecosystems are due to evolutionary adaptations to the new environmental conditions of a changing world.
Thus, the vast forests failed to evolve and adapt to the new environmental conditions, and so they disappeared, giving way to ecosystems dominated by grasslands and savannas with abundant herbaceous plants. Throughout this period, the Earth's poles were completely covered in ice, as they are today. The predominant ecosystems were those with vegetation consisting of numerous herbaceous plants, and whose most representative trees were conifers. This climate change and the resulting landforms appeared in the Miocene epoch , which is important for understanding long-term evolution.
Neogene flora
During the Neogene, there was an expansion of the life forms that had existed since the Paleogene. The Earth's climate and temperatures had a great influence on the development and establishment of new living beings. The evolution of adaptation to these environments was able to create new life forms. The fauna experienced the greatest diversification, as the flora remained somewhat stagnant due to the global drop in temperatures.
The flora was limited by the climate, which restricted the development of large-scale rainforests and even caused the disappearance of vast areas. Since large forests and jungles could not thrive in such low temperatures, plants adapted to a cold environment, such as herbaceous plants, developed. This led many specialists to refer to this period as "the age of grasses." In this context, some similarities can be observed with [the plant/plant/etc.], which also evolved under these conditions.
Some specialists refer to this period, when describing flora, as "the age of grasses." Nevertheless, many angiosperm species were able to establish themselves and thrive.
Fauna
Regarding Neogene fauna, we can see a wide diversification of many of the animal groups we know today. The most successful groups were reptiles, birds, and mammals. We cannot forget the marine ecosystems, where the cetacean group also underwent significant diversification. To understand the impact of these species, it is advisable to review the fauna of the Miocene and Pliocene epochs.
Birds of the order Passeriformes and the so-called "terror birds" were found primarily in the American continent. Today, birds of the order Passeriformes are the most diverse and extensive group of birds. This is because they have managed to survive for so long and are characterized primarily by their feet, which allow them to perch on tree branches. Furthermore, they have the ability to sing, which leads to complex mating rituals.
Of the mammals, we can say that it is the group that underwent the most extensive diversification. The entire Bovidae family, which includes goats, antelopes, and sheep, and, on the other hand, the Cervidae family, which includes deer, expanded their distribution enormously. When studying these groups, it is interesting to observe how their evolution is connected to the conditions of the [missing information - likely a specific period or stage], stages that also influenced their development.
The group of mammals that marked an extremely important event in the entire evolutionary process was that of the first hominid. It is the Australopithecus and is characterized by its small size and its bipedal movement.
