Weeds in the Anthropocene

“By the test of unwantedness, there can be no weed in the absence of man. Ecologically, we suggest that man is equally necessary for weeds to be weeds.”   Harlan and de Wet, 1965

The Anthropocene has not yet been formally recognised as a unit of geological epochs, but that hasn’t restrained its rapid spread and use in the humanities and social sciences. The term is catchy because it conveys the enormous impact that we — going by the title of the famous 1956 collection edited by William Thomas Jr., Man’s Role in Changing the Face of the Earth — as humans have made not just on, but to the Earth.

In a paper recently published in the Open Access journal Conservation & Society by lead authors Lesley Head and Jenny Atchison and a group of scholars (including Christian Kull and myself), the Anthropocene is used to highlight the reality of managing ‘environmental weeds’ in landscapes that have been enormously transformed by humans. Drawing together research and discussions held at the Wollongong Weeds Workshop in February 2013, the paper argues that rather than focusing on behaviour of ‘invasive’ plants to the exclusion of their equally invasive human agents, it is far more important to see how people actually go about managing the presence of weedy plants in their landscapes.

The key message is that most people (including those working for government agencies that are responsible for environmental and land management) recognise the futility of waging ‘constant war’ against weeds or trying to restore nature to ‘pristine’ conditions. Instead, they have developed adaptive strategies that establish boundaries of cohabitation between these weedy plants and their human counterparts. This recognition, along with the methods and strategies they have adapted and developed for managing environmental weeds, represents a sensible approach to living in the Anthropocene.

Our paper on how baobabs came from Africa to India just published in RSOS

Our paper on the history of introduction of the baobab, Adansonia digitata, from Africa to the Indian subcontinent and beyond, was published yesterday, 9th September, in the September issue of Royal Society Open Science. It is the first systematic biogeographic study ever done on the African baobab’s distribution outside the African continent, and in particular, in the Indian subcontinent and Indian Ocean region combining genetic analysis and historical information on trade and other social networks.

It is Open Access, so please download it from the RSOS website!


Another paper that combines the results of the genetic and historical analysis with the cultural traces associated with the  African diaspora in India was published earlier this year in Environment and History, Vol 21 (1).

If you want a copy of this paper, get in touch with Priya or Karen, and we’ll send it to you!

Boabs and the mystery of ancient human settlement in northwest Australia

Display at the Derby boab tree in the Kimberley (Photo: H. Rangan)

The Derby Boab Tree (Photo: H.Rangan)

In our paper just published in PLOS ONE, we show that humans were the main agents for dispersing the boab (Adansonia gregorii) in the Kimberley region of northwest Australia. We combined evidence from boab genetics and linguistic word-forms for boabs in the Aboriginal languages of the Kimberley with palaeoclimatic and archaeological studies, to reveal that these ancient settlers in the remote northwest were responsible for bringing the boabs inland as sea levels started rising dramatically 20,000 years ago.

The results of our study reveal the mystery of ancient Aboriginal settlement and interaction in the Kimberley.  Aboriginal peoples probably lived along the northwest coastal areas of the exposed continental shelf during the last Ice Age and retreated inland as these areas were flooded by rising sea levels. They carried boab fruit with them as they moved inland into central and eastern parts of the Kimberley region, and introduced the tree and associated words to other Aboriginal communities living there. Continue reading