What is the diversity of species types on Earth relating differences between known numbers and estimated numbers?

The diversity of species types on Earth is vast and encompasses a wide range of organisms, from microscopic bacteria to large mammals. While there is still much to be discovered and understood about the planet's biodiversity, scientific research and estimates provide insights into the number and variety of species. Here's an overview of the differences between known and estimated numbers of species on Earth:

1. Known Species:

- According to the Catalogue of Life, a global taxonomic database, there are currently around 1.9 million species of animals, plants, and fungi that have been formally described, identified, and documented.

- This number represents the species for which scientific names have been assigned and accepted by the scientific community.

- Known species include vertebrates, invertebrates, vascular plants, non-vascular plants, fungi, and microorganisms.

2. Estimated Species:

- Estimates of the total number of species on Earth vary widely, ranging from 3 million to over 100 million.

- These estimates take into account species that have not yet been discovered, described, or classified.

- Many of these estimates are based on mathematical models, extrapolations, and ecological research that considers factors such as habitat types, species richness patterns, and global biodiversity gradients.

3. Factors Affecting Estimates:

- The uneven distribution of species across different geographical regions and habitats makes accurate estimates challenging.

- Some regions, such as tropical rainforests, are known for their high biodiversity, while others, like deserts, have lower species diversity.

- The cryptic nature of certain species, where they may be difficult to observe, identify, or distinguish from similar species, also contributes to uncertainties in estimating total species numbers.

4. Undiscovered Species:

- It is estimated that a significant number of species remain undiscovered, especially in unexplored ecosystems, such as deep-sea environments, caves, and remote forests.

- Ongoing scientific expeditions, research, and advances in technology continue to reveal new species regularly, expanding our understanding of Earth's biodiversity.

5. Challenges in Classification:

- As scientists continue to study and classify species, revisions and updates to taxonomic classifications may occur, leading to changes in species counts and names.

- The process of species identification and delimitation can be complex, especially in cases of closely related or cryptic species.

It is important to note that these estimates and known numbers are subject to change as new species are discovered, and scientific knowledge continues to evolve. Ongoing research and conservation efforts are essential to better understand, document, and protect the incredible biodiversity that exists on Earth.