Strong environmental forcings, from storms to fires and insect outbreaks to elephants, drive tree population dynamics in forests across the world. Despite the pervasiveness of these environmental drivers, most theoretical models of forest tree dynamics ignore them, focussing instead on neutral drift and niche stabilisation. What effect does environmental variance have on patterns of forest diversity? In our new paper, in press at Ecology, we show that a model with realistically strong environmental forcings can accurately reproduce both static and dynamic patterns of diversity in two tropical forest plots, one in Malaysia and one in Panama. This is superior to previous similar models that are unable to capture both types of diversity simultaneously—for example, neutral models are only able to realistically produce static patterns such as species-abundance distributions. Our work further underscores the need to include strong components of environmental variance in realistic models of tropical forest dynamics.

This work was led by Tak Fung, with Kassim Abd. Rahman and Christine Fletcher (Forest Research Institute Malaysia), and James O’Dwyer (Univ. of Illinois) as a collaborators.

Reproducing static and dynamic biodiversity patterns in tropical forests: the critical role of environmental variance. Tak Fung, James P. O’Dwyer, Kassim Abd. Rahman, Christine D. Fletcher and Ryan A. Chisholm, in press, Ecology.

Poulsenia armata, a tree that was formerly dominant in the canopy at the Panama plot but suffered 50% mortality during a 1980s drought (image credit: biogeodb.stri.si.edu).

A new article on Mongabay discusses the potential for drones and other automated technologies to be used for forest restoration. It covers recent developments in the field of automated forest restoration, including last year’s Chiang Mai workshop and our forest drone trials.

Forest restoration: from Stone Age to drone age

Forest restoration: from Stone Age to drone age

Photo by S. Elliott

Ryan has just returned from France, where he gave a series of guest lectures and workshops to the Erasmus Mundus International Master in Applied Ecology programme at the University of Poitiers. This Masters programme draws in students from all around the world and allows students to rotate between different countries in the European Union over two years.

Ryan also visited and presented seminars at Jerome Chave’s lab at the University of Toulouse and at the Station for Theoretical and Experimental Ecology in Moulis, nestled in the foothills of the Pyrenees.

Our new termite evolution paper, led by Thomas Bourguignon, is now online at American Naturalist. The ancestors of termites were solitary cockroaches. Around 170 million years ago, something drove these cockroaches to become social and to have distinct castes. What were these driving forces and in what steps did termite evolution proceed? In bees and wasps sociality evolved first, and the distinct castes evolved second. In our new paper, we argue that the reverse occurred in termites. We present evidence that the first step in termite evolution was the appearance of a new wingless body type, as an alternative, terrestrial, strategy to the ancestral winged body type. The new wingless body type minimised the risks of aerial predation when dispersing. We propose that sociality in termites evolved only after the winged–wingless diphenism was well established.

Bourguignon, T., Chisholm, R.A. & Evans, T.A. (in press). The termite ‘worker’ phenotype evolved as a wingless dispersal strategy before eusociality. The American Naturalist.

Individuals of the basal termite species, Mastotermes darwiniensis, including (A) a large juvenile nymph with smaller wingless non-reproductive workers, (B) winged reproductives (kings and queens), and (C) wingless reproductives. Photos by David McClenaghan, released on Commonwealth Scientific and Industrial Research Organization ScienceImage under the Creative Commons Attribution 3.0 unported license.

Many species are known to have vanished from the Earth over the last few hundred years. Over the same period, many new species have been discovered. Logically, there must be some species that went extinct without ever being discovered. How can we estimate these “undetected extinctions”? In a paper just published in Conservation Biology, we provide a new method for doing so. Our method is more flexible than previous methods because it does not rely on strong assumptions about extinction and detection rates being constant over time. Our method can be applied at both global and national levels.

We apply the new method to Singapore’s bird fauna over the last 200 years and estimate that, in addition to the 58 known extinctions out of 195 total known bird species, a further 9.6 species have gone extinct without ever being discovered (with a 95% confidence interval of [3.4, 19.8]).

Chisholm R.A., Giam X., Sadanandan K.R., Fung T. & Rheindt F.E. (2016). A robust non-parametric method for quantifying undetected extinctions. Conservation Biology.

The Scarlet-rumped Trogon (Harpactes duvaucelii) could conceivably be one of Singapore’s undetected extinctions: it is common in forests in nearby Johor but was never observed in Singapore itself (Photo credit: David Tan).

Catharina has been awarded a grant from the National Geographic Society. The grant will be used to set up automatic acoustic monitoring stations at her field sites on Mount Kinabalu and to support standard visual encounter survey work. She expects automatic acoustic monitoring to be more cost effective than visual surveys because of the steep terrain and dense vegetation. The stations set up for acoustic monitoring will also gather additional environmental data, such as humidity and temperature, which will then be transmitted back to a server. Catharina will also be working on developing new algorithms for classifying frog calls using a Bayesian framework.

Lin Yuan’s haze research has been featured in The Straits Times. She is conducting a willingness-to-pay survey for haze mitigation in Singapore using both face-to-face and online surveys. The information from the surveys will help form a picture of the impacts of the haze on Singaporeans.

Nega and Catharina recently attended the 20^th Biological Sciences Graduate Congress in Bangkok, Thailand. Nega presented a talk titled “The role of bird traits in predicting bird shifts in response to climate change” and Catharina presented a poster titled “Optimal Monitoring and detection of Amphibians on Mount Kinabalu”. The congress was a good opportunity to interact with graduate students from the other two Asian universities involved as well as with students in other biological disciplines from NUS.

Catharina has received a grant from the Mohamed bin Zayed Species Conservation Fund. The grant was awarded to support her work on the Luidan stream toad (Ansonia platysoma) in Kinabalu Park in Sabah (Malaysian Borneo). The Luidan stream toad is listed as endangered by the IUCN and there is limited information available on its habitat requirements. Catharina will be deploying iButtons to monitor temperature and humidity in sites where the species lives as well as in areas where it is not known to occur. She will also record general habitat characteristics to obtain a clearer picture as to why this species’ distribution is so restricted.

A. hanitschi, a species closely related to A. platysoma.

Mount Kinabalu

Our editorial about Indonesia’s disastrous 2015 forest fires is now online at Conservation Biology. We discuss the causes and impacts of the fires, with a focus on regional haze and global climate change. We argue that Indonesia’s forest fires are unlikely to be mitigated by national or regional action alone and that the best hope for long-term solutions lies in REDD+ and other international efforts to combat climate change.

Chisholm, R.A., Wijedasa, L. & Swinfield, T. (in press). The need for long-term remedies for Indonesia’s forest fires. Conservation Biology

Smoke over Southeast Asia on 24 September 2015 (image from NASA).

Haze in Singapore on 6 October 2015.