The Paleontology is the science which studies fossil organisms in order to know what the past of life on our planet. Several branches arise from this discipline: palaeoecology, palaeozoology, and paleobotany. Paleoecology allows us to know what ecosystems were like in the past and what their evolution has been throughout geological time. Research in paleoecology arrived late in Spain, compared to other countries and the evolution of other sciences. In fact, its inclusion in the Spanish Association of Terrestrial Ecology (AEET) is still incipient. Therefore, it is normal that you do not know the concept of paleoecology or that you have ever wondered, when hearing its name, what paleoecology studies.
What is paleoecology and its characteristics
Following the definition of paleoecology , we could say that it is the science in charge of studying the relationship that fossil biota has with its environment and how it has evolved over time. With this, it is possible to reconstruct our planet’s own environments and ecosystems throughout the different geological eras, which is the main objective of paleoecology .
This branch of paleontology, which favors a greater understanding of the interactions between the ecological and the evolutionary, is based mainly on the analysis of pollen and fossil spores , that is, on palynology. But what does this technique consist of? Since the beginning of the last century, through the palynological method , scientists have been and are capable of identifying and describing the changes that vegetation undergoes (density, height, shape, adaptations, etc.) with climatic variations (temperature, salinity, solar radiation, humidity, etc.).
Some of its characteristics of paleoecology are:
- Identify patterns that have occurred throughout history in the functioning of ecosystems and their biodiversity (for example: relationships between sizes of organisms and environmental temperature).
- Expands knowledge in relation to the exploration and development of natural resources.
- It allows to know the way of life and the habitat of the fossils either individually through paleoautoecology (species, populations) or jointly through synecology (communities).
- It complements ecological studies, where time is a hardly explored dimension.
In order to recreate environments and ecosystems, paleoecology is normally based on statistical inferences and mathematical modeling . To do this, it uses as a knowledge base data and information about the species that we currently know and that have a certain kinship with the fossil organisms under study.
In the specific case of the palynological method, to study pollen and spores, substances such as hydrochloric acid, hydrofluoric acid and nitric acid are used in the laboratory . Once the samples have been prepared, they are observed using an optical microscope or a scanning electron microscope. In the case of non-pollen fossils, such as those of aquatic organisms (such as algae , bacteria , zooplankton ) contained in sediment, the dating is done through microscopic analysis. With this laboratory analysis, organisms that have succeeded each other from the oldest deep levels of the sediment to the most current can be identified.
To summarize the importance of paleoecology, we take these aspects into account:
- In the first place, paleocology can be useful to determine the primordial origin and taxonomic relationships of the flora and fauna of each geological era . For example, a study carried out by the University of Florence, the National Museum of Eritrea and the IPHES (Institut Català de Paleocologia Humana i Evolució Social) in 2009 establishes the evolutionary line of a bullfighting ancestor, specifically of the Bos genus, corresponding to the Pleistocene.
- On the other hand, taking into account that the past determines the present, paleoecology is important because it allows us to understand the functioning of natural systems and to foresee how they can respond to certain climatic conditions. For example: we can know what is the recurrence of fires, floods and other risks in certain areas; We can find out what are the climatic conditions that have led to the previous great extinctions and establish relationships with those that trigger the sixth great extinction already underway.
- It also provides information on how human impacts have influenced the environment and the configuration of landscapes throughout history.
- It also makes it possible to differentiate which are the invasive species and the native species of the ecosystems. For example, thanks to paleoecology it is known that the European chestnut is a native plant of Galicia since there is evidence of its presence dating back to the Tertiary, the Upper Pleistocene and the Holocene.
- Finally, paleoecological studies can contribute to the formulation and design of measures for the conservation of biodiversity .