A new study by a University of Exeter researcher has shed light on how an estimated one million-strong population of wild camels thriving in Australia’s remote outback have become reviled as pests and culled on a large scale.Sarah Crowley, of the Environment and Sustainability Institute at the University of Exeter’s Penryn Campus, explored the history of the camel in Australia, from their historic role helping to create the country’s infrastructure through to their current status as unwelcome “invader.”The deserts of the Australian outback are a notoriously inhospitable environment where few species can survive. But the dromedary camel (Camelus dromedarius) prospers where others perish, eating 80% of native plant species and obtaining much of their water through ingesting this vegetation.Yet for numerous Australians, particularly ranchers, conservation managers, and increasingly local and national governments, camels are perceived as pests and extreme measures — including shooting them with rifles from helicopters — are being taken to reduce their population.In her article, published in the journal Anthrozos, Crowley proposes that today’s Australian camels exemplify the idea of “animals out of place” and discusses how they have come to inhabit this precarious position.She said: “Reports estimate there are upwards of a million free-ranging camels in Australia and predict that this number could double every eight years. As their population burgeons, camels encroach more frequently upon human settlements and agricultural lands, raising their media profile and increasing local animosity toward them.”The camel was first brought to Australia in the 1800s when the country was in the midst of a flurry of colonial activity. The animals were recognized by pioneers as the most appropriate mode of transport for the challenging environment because they require significantly less water, feed on a wider variety of vegetation, and are capable of carrying heavier loads than horses and donkeys.Camels therefore played a significant role in the establishment of Australia’s modern infrastructure, including the laying of the Darwin-Adelaide Overland Telegraph Line and the construction of the Transnational Railway.Once this infrastructure was in place, however, and motorized transport became increasingly widespread, camels were no longer indispensable. In the early part of the 20th century they rapidly lost their economic value and their displaced handlers either shot their wards or released them into the outback where, quite discreetly, they thrived.It was not until the 1980s that surveys hinted at the true extent of their numbers, and only in 2001 that reports of damage caused by camels were brought to the general populace.Camels are not the most dainty of creatures. Dromedaries are on average six feet tall at the shoulder, rendering cattle fencing no particular obstacle to their movement. By some accounts, camels may not even see small fences and consequently walk straight through them.Groups of camels arriving on agricultural properties and settlements in Australia, normally in times of severe drought, can also cause significant damage in their search for water.In 2009, a large-scale culling operation began. There were objections from animal welfare groups and some landowners who were concerned that the method of culling from helicopters, leaving the bodies to waste, is inhumane. Most objectors, however, were primarily concerned that culling is economically wasteful and felt that the camels should be mustered for slaughter or export.There are also concerns regarding the global environment, as camels may contribute to the desertification of the Australian landscape. They are also ruminants and thus produce methane, adding to Australia’s carbon emissions. …Read more
Tropical montane rain forests are highly threatened and their remnants are often surrounded by deforested landscapes. For the regeneration of these degraded areas, seed dispersal of forest trees plays a crucial role but is still poorly understood. Most tree species are dispersed by birds and mammals, but also by ants. A study published today in the Journal of Ecology by a team from the LOEWE Biodiversity and Climate Research Centre and the University of Halle-Wittenberg demonstrates the importance of this hitherto neglected ecosystem function for the restoration of montane rain forests. Ants promote the regeneration of these forests by dispersing seeds to safe sites for tree establishment.The Yungas, a region on the eastern slopes of the Bolivian Andes near La Paz, are marked by elongated valleys with relicts of the original mountain rain forest. Due to land-use practices like slash-and-burn agriculture and the extension of coca plantations, the forests are highly fragmented. The forest relicts are surrounded by an open, largely degraded cultural landscape. In this context, the team conducted experiments to find out to what extent ants contribute to the dispersal of a widespread, primarily bird-dispersed tree (Clusia trochiformis) and tested whether this ecosystem function may contribute to the restoration of deforested areas.The red, lipid-rich aril, a fleshy pulp surrounding the seeds of Clusia, is highly attractive to many animals. Birds are the primary dispersers. They feed on the nutritious part of the fruits, the fleshy aril, and defecate the seeds. …Read more
Protected natural areas in Costa Rica reduced poverty by 16 percent in neighboring communities, mainly by encouraging ecotourism, according to new research published today in the Proceedings of the National Academy of Sciences.Although earlier studies indicated that establishing protected areas in poor regions can lead to reductions in poverty, there was no clear understanding why or how it happens.”Our goal was to show exactly how environmental protection can reduce poverty in poorer nations rather than exacerbate it, as many people fear,” says co-author Paul Ferraro, a professor of economics and environmental policy in the Andrew Young School of Policy Studies at Georgia State University.In their article, “Quantifying causal mechanisms to determine how protected areas affect poverty through changes in ecosystem services and infrastructure,” Ferraro and Georgia State alumnus Merlin Hanauer, now on the Economics faculty at Sonoma State University, examine three potential causes of poverty reduction linked to the establishment of protected areas:changes in tourism and recreational services, changes in infrastructure including roads, health clinics and schools, and changes in ecosystem services such as the pollination and hydrological services a protected area may offer. They find that increased tourism accounts for two-thirds of the reduction in poverty caused by protected areas. Changes in infrastructure and land use had little effect on the poverty in surrounding communities.”Our results suggest that by using existing data sets such as poverty estimates from census data, the impacts of conservation programs and policies on human populations can be better defined,” says Ferraro. “Our findings may result in improved conservation programs and policies, and better impacts on the communities adjacent to these sites, locally and around the globe.”Story Source:The above story is based on materials provided by Georgia State University. Note: Materials may be edited for content and length.Read more
A new study by a Wits University scientist has overturned a long-standing hypothesis about plant speciation (the formation of new and distinct species in the course of evolution), suggesting that agricultural crops could be more vulnerable to climate change than was previously thought.Unlike humans and most other animals, plants can tolerate multiple copies of their genes — in fact some plants, called polyploids, can have more than 50 duplicates of their genomes in every cell. Scientists used to think that these extra genomes helped polyploids survive in new and extreme environments, like the tropics or the Arctic, promoting the establishment of new species.However, when Dr Kelsey Glennon of the Wits School of Animal, Plant and Environmental Sciences and a team of international collaborators tested this long-standing hypothesis, they found that, more often than not, polyploids shared the same habitats as their close relatives with normal genome sizes.”This means that environmental factors do not play a large role in the establishment of new plant species and that maybe other factors, like the ability to spread your seeds to new locations with similar habitats, are more important,” said Glennon.”This study has implications for agriculture and climate change because all of our important crops are polyploids and they might not be much better at adapting to changing climate than their wild relatives if they live in similar climates.”Glennon’s study also provides an alternative explanation for why plants are so diverse in places like the Cape where the climate has been stable for hundreds of thousands of years. Although her study examined plant species from North America and Europe only, she is looking forward to testing her hypotheses using South African plants.Glennon’s paper has been published in Ecology Letters.Story Source:The above story is based on materials provided by Wits University. Note: Materials may be edited for content and length.Read more
July 4, 2013 — The earliest evidence of using flower beds for burial, dating back to 13,700 years ago, was discovered in Raqefet Cave in Mt. Carmel (northern Israel), during excavations led by the University of Haifa. In four different graves from the Natufian period, dating back to 13,700-11,700 years ago, dozens of impressions of Salvia plants and other species of sedges and mints (the Lamiaceae family), were found under human skeletons.”This is another evidence that as far back as 13,700 years ago, our ancestors, the Natufians, had burial rituals similar to ours, nowadays,” said Prof. Dani Nadel, from the University of Haifa, who led the excavations.The Natufians, who lived some 15,000-11,500 years ago, were of the first in the world to abandon nomadic life and settle in permanent settlements, setting up structures with stone foundations. They were also among the first to establish cemeteries — confined areas in which they buried their community members for generations. The cemeteries were usually located at the first chambers of caves or on terraces located below the caves. In contrast, earlier cultures used to bury their dead (if at all) randomly. Mt. Carmel was one of the most important and densely populated areas in the Natufian settlement system. Its sites have been explored by University of Haifa archeologists for dozens of years.A Natufian cemetery containing 29 skeletons of babies, children and adults was discovered at Raqefet cave. …Read more
May 28, 2013 — When University of Alberta researcher Catherine La Farge threads her way through the recently exposed terrain left behind by retreating glaciers, she looks at the ancient plant remains a lot closer than most. Now, her careful scrutiny has revealed a startling reawakening of long-dormant plants known as bryophytes.
La Farge, a researcher in the Faculty of Science, and director and curator of the Cryptogamic Herbarium at the University of Alberta, has overturned a long-held assumption that all of the plant remains exposed by retreating polar glaciers are dead. Previously, any new growth of plants close to the glacier margin was considered the result of rapid colonization by modern plants surrounding the glacier.
Using radiocarbon dating, La Farge and her co-authors confirmed that the plants, which ranged from 400 to 600 years old, were entombed during the Little Ice Age that happened between 1550 and 1850. In the field, La Farge noticed that the subglacial populations were not only intact, but also in pristine condition — with some suggesting regrowth.
In the lab, La Farge and her master’s student Krista Williams selected 24 subglacial samples for culture experiments. Seven of these samples produced 11 cultures that successfully regenerated four species from the original parent material.
La Farge says the regrowth of these Little Ice Age bryophytes (such as mosses and liverworts) expands our understanding of glacier ecosystems as biological reservoirs that are becoming increasingly important with global ice retreat. “We know that bryophytes can remain dormant for many years (for example, in deserts) and then are reactivated, but nobody expected them to rejuvenate after nearly 400 years beneath a glacier.
“These simple, efficient plants, which have been around for more than 400 million years, have evolved a unique biology for optimal resilience,” she adds. “Any bryophyte cell can reprogram itself to initiate the development of an entire new plant. This is equivalent to stem cells in faunal systems.”
La Farge says the finding amplifies the critical role of bryophytes in polar environments and has implications for all permafrost regions of the globe.
“Bryophytes are extremophiles that can thrive where other plants don’t, hence they play a vital role in the establishment, colonization and maintenance of polar ecosystems. This discovery emphasizes the importance of research that helps us understand the natural world, given how little we still know about polar ecosystems — with applied spinoffs for understanding reclamation that we may never have anticipated.”
The research was published in the Proceedings of the National Academy of Sciences.Read more