This Blog post #6 is entitled: Biodiversity – Functions. It follows our last post #5: “Biodiversity – Evolution” of this Biodiversity series.
This present post is inspired by chapter 4, “Functions”, of Antonelli’s book, “The Hidden Universe: Adventures in Biodiversity”.
Biodiversity – Functions
In Chapter 4 of his book, Antonelli recounts of his early experience gained assisting scientists in Lapland, 200 kilometres or so north of the Polar Circle. He uses this experience of studying the arctic ecosystems to introduce the reader to ecological function, the ways in which differing species affect their environment and interact with other species. The research produced insights into changes in functional diversity induced by the effects of climate change on the local environment.
Changes over extremely short periods of time
The research showed that climate change was causing visible and substantial changes in the functions of plant and animal communities.
Fourth Axis of Biodiversity
Antonelli explains that functional diversity variable is the fourth axis of biodiversity, and that this is intrinsic to the living species on Earth. It is often the first variable to change as the environment changes.
Narrowing of Functions
He points out that unfortunately, as climate changes and certain plant species take over large areas in an ecosystem, out competing others, this can bring about a narrower set of functions than the original species. He points out that: “Functional diversity is critical to maintaining a natural world full of variety and difference”.
Difficult to Measure Functions
The picture is complex and it is very difficult to identify and measure every function that a species plays. Antonelli quotes the example of growing forests around the world to slow down climate change. He states that the potential for trees to help capture carbon is uncertain. The unknowns include lack of accurate assessments of carbon content in the wood of the world’s more than 70,000 known tree species and how much carbon trees can store under the ground in their root systems and carbon storage.
Redundancy
Antonelli explains that an interesting aspect of functional diversity is redundancy. This is where different species have overlapping functions with the result of a surplus of a function in a particular ecosystem. He asks whether this is a good or bad thing? He then gives an example from the Caribbean involving research into three million year old mollusc fossils.
The molluscs suffered an unknown extinction event and as a consequence of the large degree of functional diversity amongst the species of molluscs, only 3% of functionality was lost from the whole ecosystem despite losing half of the number of different species.
Abundance of Functions
When there is an abundance of functions from various species and complex food webs within an ecosystem, the ecosystem is more healthy and resilient to climate change. In effect, there is an extra layer of insurance so that even if some species go extinct functional diversity remains.
Summary
Antonelli concludes that functional diversity provides a bridge between the smallest components of biodiversity (species and their genes) and the largest of them (ecosystems).
The next Blog post, #7 of this series, will be entitled: “Biodiversity – Ecosystems” and will be inspired by chapter 5, “Ecosystems”, of Antonelli’s book, “The Hidden Universe: Adventures in Biodiversity”.
(Post Dated: 9/05/2026)