What Is Paleobotany? - Study of Plant Fossils
Many of us think of dinosaurs when we think of fossils, these terrifying animals often most capturing the imagination. However, all types of life have been fossilized. These are no less important in terms of the evolutionary development of our planet. Plant fossils are the preserved remains of prehistoric botanic life which can reveal much about the geological eras Earth has experienced. The study of plant fossils is known as paleobotany, a discipline of botany which deals with the evolutionary history of plants.
At thedailyECO, we learn about what is paleobotany? We understand how plants become fossils, the types of plant fossils that exist and why studying plant fossils is so important.
What does paleobotany study?
We start by providing a definition of what paleobotany is. Paleobotany is broadly defined as the science that studies the fossil remains of plant species that lived over 10,000 years in the past. It is a subdiscipline of botany, but is also related to paleontology. In fact, we can consider paleobotany to be somewhat fo a cross-discipline between paleontology and botany.
Although this is a basic definition of paleobotany, it is a broad subject which contains various fields of study within its remit. For example, it is very important in plant anatomy and morphology, but it also provides vital information for the study of evolutionary biology.
One of the most important factors involved in paleobotany is the ecological approach to its study. For this reason, it is often studied across the discipline of paleoecology. This is the study of how organisms interact with each other and their environments in prehistory. In this way, it considers how species adapt to larger ecosystems, something which is very important in terms of phytogeography.
By understanding how these different disciplines interact with paleobotany, we can generate a clearer picture of how different geoglocial eras existed. In turn, this can also help us understand how present day ecosystems evolve and change.
Learn about the oldest extant land plants with our article on what are hornwort plants?
How plants fossilize
The fossil records of dinosaurs and other animals are possibly better known than plant fossils. For example, we may be aware of ammonites from the sea, but can't name a specific plant fossil. However, there are many fossil records of plants that make the study of paleobotany possible.
The fossilization process itself is possible thanks to the cell wall present only in plant cells. Unlike animals which have an extracellular matrix, plants have wall in their cells which acts as an external skeleton, giving the cell a certain degree of rigidity.
Furthermore, the cell wall mainly consistes of cellulose combined with hemicellulose and lignin. These are three compounds that do not degrade easily in nature, which is a characteristic that favors the fossilization process. For this reason, plants are often better preserved in fossils than animals. Learn more about the difference between animal and plant cells in our related guide.
Although they generally fossilize better than animals, plants can fossilize in different ways. This gives rise to different types of plant fossils. In the next section, we will develop the diversity of plant fossils that have been found in nature.
Types of plant fossils
As we mentioned in the previous section, fossilized plants are produced in different ways and give rise to different types of fossils. Some of the most common types of plant fossils include:
- Permineralizations: permineralizations is a type of petrification in which plant cells are filled with a fluid composed of silica or other minerals. This solidifies over time and becomes rock. In this way, the fossils are practically perfect since they preserve their shape, structure and, in some cases, the characteristics of their tissues. The organs that most frequently suffer permineralization are the stems, trunks and roots, as well as fruits and seeds.
- Impressions: this is due to a type of fossilization that occurs when the leaves or other parts of the plant fall and leave an impression. Specifically, they leave an imprint on a soft surface that solidifies over time. From the impressions, it is possible to find plant fossils within stones. These are mainly leaf fossils. It can also happen that after the impression, the plant tissue does not completely disintegrate. In these cases, it can leave a film of organic compounds on the impression or footprint. This is known as impression-compression.
- Molds: sometimes it happens that plant remains fall and are covered by soil. Over time, these degrade and leave a space in the rock that constitutes the mold. Such molds are often filled with sediment or other compounds.
- Mummifications: pollen grains and spores fossilize as mummifications. However, pollen and spore fossils are not directly studied in paleobotany, but rather in the related field of paleopalynology.
You can learn more about the types of fossilization and fossil preservation in our related article.
Importance of paleobotany and its applications
Paleobotany is a discipline of high importance. In addition to allowing us to understand the origin of current plant species, it helps shed light on their relationships and their distribution. Its studies also allow us to know the changes in the history of the planet, since plant fossils usually characterize the different stages of geological development on Earth.
As a result of this, one of the applications of paleobotany is in stratigraphy, a branch of geology that studies the arrangement and characteristics of the different strata and sedimentary rocks of the Earth's surface. In general, the fossils used to understand stratigraphy are so-called guide fossils. These are types of fossils that existed for a short time and were distributed over wide geographic areas.
Now that you know better what paleobotany is, we encourage you to learn more about how animal fossils provide information in the past with our article on how many kinds of dinosaur were there?
If you want to read similar articles to What Is Paleobotany? - Study of Plant Fossils, we recommend you visit our Biology category.
- Archangelsky, S. (1970). Foundations of paleobotany.
- Martínez, L. C., & Ruiz, D. P. (2016). Fossil plants teach us the history of the Plant Kingdom.