Birds and landscape histories

Finds tongues in trees, books in the running brooks,
Sermons in stones, and good in everything.
I would not change it. 

Most traditional historians do not see much use for science but there are now growing branches of science that are essentially about determining histories. These include histories of climate, habitat connectivity, and the evolution of organisms. The field of phylogeography attempts to look at the distributions and evolutionary relationships of a cluster of inter-related species to see patterns in their diversification, examine timing and relationship to environmental or climatic changes. Past vegetation  can be guessed by the signs left by plants through pollen deposits in certain kinds of preserving environments like peat bogs. A cylindrical core extracted from the bog tells us something about the vegetation of the older period, the deeper layers being older, with the time itself estimated by carbon dating. Every organism has a book in the form of DNA and the lines in this book are constantly being edited with copy pasting as the organisms reproduce and accumulate mutations (typos and copying errors). By looking at the edit history of specific sections of DNA across sample individuals, it is possible to reconstruct a chronological sequence of the edits (the way to establish what is recent versus what is older requires a trick that requires prior knowledge, a sample of a script that is decidedly older - an individual known as an outgroup). In addition to regular nuclear DNA, there is DNA in the mitochondria which passes from mother to offspring and this is generally conserved with occassional changes caused by mutations (largely but introgression is known). The history of mutation accumulation can help reconstruct chronologies. There are of course many little problems, histories lost through extinction of lineages, and corrupted histories resulting from unrelated DNA being inserted by viruses or bacteria that break expectations of linearity. Histories of human movement have been found by examining DNA across peoples.

Histories at different scales and for varying epochs can be read from diverse sources. Igneous rocks can tell the pressure, temperature and rate of cooling around them by the sizes of the crystals formed within them and their mineral compositions. Sedimentary rocks hold fossils in the leaves of their pages. Trees keep note of fires and environmental conditions in their rings. Bubbles trapped in polar ice have been the source of atmospheric composition history.

The sources for history therefore go well beyond what archaeologists and traditional historians would want to preserve. It is a pity however that these other sources get so little attention among historians. 

 

Few can appreciate the oddity of this specimen from Antharasanthe near H.D. Kote, Karnataka

I recently visited the Regional Museum of Natural History at Mysore along with Dr Robert Prys-Jones of the Natural History Museum at Tring and thanks to his presence, I was, reluctantly, allowed to go behind the scenes and take a peek at some bird specimens that Salim Ali had collected in the late 1930s. [I had been at the RMNH many years ago with the late S.A. Hussain when this collection was moved there and I have since always been irritated by government officials preventing access to such collections across India. We arguably have a system worse than colonialism!] One of the specimens that caught my attention was of a black-headed babbler / dark-fronted babbler (Rhophocichla atriceps). It was collected by Salim Ali in 1939 from Antharasanthe. I have passed through Antharasanthe many times in recent years and for someone who knows the bird and the kind of habitat in which it is normally found, it is simply mind-boggling to imagine that Antharasanthe once had dense forests with a dark and dense undergrowth. This is something that few can appreciate and it requires a knowledge of the bird in question.

Clearly not all sources of history can be appreciated or understood by traditionally trained historians. There is a classic example of such ineptitude provided by Delhi-based historians Romila Thapar and Valmik Thapar who, in their book Exotic Aliens – The Lion and Cheetah in India, claim that lions and cheetahs in India were introduced from Africa in fairly recent times by local rulers. This of course can easily be dismissed by looking at DNA evidence and the book of course has since been repeatedly and confidently dismissed by scientists.

In April 2016 I had the privilege of walking along a Himalayan hillside with Emmanuel Theophilus and S. Subramanya and we came across trees with curious swollen rings on their trunks. Observing them closely showed that there were series of punctures made over these rings by woodpeckers. There are a group of woodpeckers in North America that are called sapsuckers - they all belong to the genus Sphyrapicus and have the habit of making punctures on trees and waiting for sweet sap to fill them up. They revisit these holes and sip the sap that collects. Now there is just one species in Asia that has the same habit - the rufous-bellied woodpecker and even called the rufous-bellied sapsucker (Dendrocopos hyperythrus) - and it leaves a trace on the trees. They are not produced by single individuals but by generations of them. The trees which are at least a century old have rings that are tapped repeatedly and the calluses grow quite wide due to the repeated injury. Not all trees seem to respond to the damage in the same way and the most significant callusing was found in karsu oak and rhododendrons (they are massive trees here, worth mentioning for readers familiar only with rhododendrons from higher latitudes). Interestingly Green-tailed sunbirds (Aethopyga nipalensis) seem to be secondary sapsuckers and they hover and steal sap from the same puncture sites.

Emmanuel Theophilus points to calluses on karsu oak Quercus semecarpifolia

Callus rings on a Rhododendron

Rings from at a distance.

 

Close up of a ring showing a fresh line of punctures.

Perhaps there are places in the Himalayas where the woodpeckers have left their traces and vanished since and hopefully those histories that are not lost to the timber trade.

There is then a case for historians to learn a bit of ornithology and there is of course a case to be made for ornithologists to know a little bit of history. The latter is probably harder considering that hordes  contribute to such systems a ebird with no standards for the recording of habitat conditions. It is as if they assume that habitats are static. If anything has been learned by looking at old bird literature it is the inability to guess what kind of a habitat a bird formerly used. Standards for describing habitats that can guide future work and that which can be analyzed quantitatively has to be evolved locally, it involves democratizing citizen science websites and therein lies the problem. History, even of humans, is important for software designers, as much as it is for scientists.

 

Postscript: 5-Sep-2024 found this - Baral, H.S. 2023. Ecosystem engineering: Rufous-bellied woodpecker Dendrocopos hyperythrus (Vigors, 1831) modifying tree shapes of Himalayan broadleaved forests. Nepalese Journal of Zoology, 7(2):1–7.