Global plant diversity

Our latest paper (here) in the prestigious journal Nature Communications is about global patterns of plant diversity. Species richness is usually described with alpha diversity (number of species in a plot), beta diversity (change of species among plots) and gamma diversity (regional to continental number of species). This paper is about alpha diversity.

The number of species found in a plot is related to the plot size. As any chosen plot size is arbitrary, the question was to check how alpha diversity would change with different plot sizes (also called grain) and how the alpha diversity measured at different grains would be distributed over the world. The number of species was also correlated to climate, soil and topography.

Global maps of alpha diversity were produced from more than 170,000 plots worldwide. The number of species in these plots was extracted at three different scales (say small, medium and large).

The maps of alpha diversity worldwide classically show an increase of local diversity from the temperate to the tropical regions. However, the three grains do not exactly produce the same maps, which shows that alpha diversity is not accumulated at the same rate from region to region. The African forests have high coarse grain richness whereas Eurasian temperate forests have high fine grain richness. The cause of these differences are still unknown and among the potential candidates are: history, species assembly rules, selection.

India’s plant alpha diversity in general is intermediate with a regular accumulation of species from fine to coarse grain. The North-East and a small part of the Himalayas have a very high alpha diversity at small grain but not at coarse grain. Alpha diversity hotspots are small or non-existent even though the gamma diversity is intermediate in the Western Ghats and the assemblage unique due to endemics.

It should be noted that non-forest plots appear as data deficient in north India: is it because data could not be found online or because there are too few studies on vegetation?

Jean-Philippe Puyravaud

A tribute to Bellan, Forest Watcher

Bellan, Forest Watcher, on the right.


Nassim Taleb, one of my favorite authors, wrote about heroes in his book “The Black Swan”. He said something a bit startling: if an administrator had taken the proper safety steps, the destruction of the Twin Towers in New York may not have happened. This administrator would have been a hero but no one would have known because nothing would have happened in the first place. Heroes are characterized first by their sense of duty.

The term “wildlife hero” we hear too often has become overused. We see so much craving for fame in the little world of conservation that any designated wildlife hero will suddenly believe in a stratospheric status and never come back to earth.

Mr. Bellan, a simple forest watcher, who died at sixty a few weeks ago, was not into self-promotion. Of humble origin, he never expected rewards and he would have been astonished to see that people took an interest in him. He was from a family of shikaris and had a deep, intuitive understanding of wildlife.

The first time I met Bellan was when I had been charged by an angry elephant. People had burst fire crackers near our house and I wanted to tell them to stop disturbing the elephant which was around. Unfortunately, I did not know the elephant’s exact location and he charged on seeing me. It was a miraculous escape. Bellan came when we complained about the fire crackers and we told him the story. He also had escaped an attack. The elephant stepped on him, breaking a few ribs. It took him six months before he recovered from the shock, even though he looked tough. This was sort of healing for me to realize that to be unsettled under these circumstances was natural.

Recently, Bellan had to take charge of Rivaldo, the local elephant star. Rivaldo is radio-collared and constantly under supervision to make sure he does not get fed by people. Every time Rivaldo decided to come to drink at our tank, we could meet with Bellan. It was fascinating because he knew the jungle just like the old folks. We were so happy to see a person with whom we could share our ideas and be understood. For example, we hide when we see Rivaldo. So many of the forest staff who were noisy and fully visible to the elephants, mistook our behavior for something else. They thought we were frightened when in fact we just prefer elephants not to get used to human presence. Bellan understood why we were going away and he himself was quiet and inconspicuous.

Bellan told us that the anti poaching watchers were insufficiently trained to be in the jungle. We could not agree more with him. The watchers are a walking disturbance now armed with their mobile phones with which they keep on taking selfies and probably post the pictures on social media. We have seen watchers being charged when the provocation was completely avoidable. So, he trained them and did what he could given that he was in the lower rank of the hierarchy.

Earlier, Bellan was requested to follow Ronaldo who was the most powerful and aggressive tusker in the region. Ronaldo had been injured on his back the first time, and on the second time a flaming object was thrown on him. The elephant suffered and died in agony. Bellan was the man who was saying a tearful goodbye if you read “Tamil Nadu forester bids emotional goodbye to dead elephant link required. Watch a heart-wrenching video.”* His name never appeared in the paper. If I can speak for Bellan who is no more, his tears may not have been only because he was a sensitive guy who liked elephants, but also because many such incidents could be avoided. The newspaper said Bellan was a Ranger. He was only a Watcher. People of his capability don’t get promoted. And, yes, he was a hero.

Jean-Philippe Puyravaud.

*We never watched the video. We knew too well what it was to lose Ronaldo.