Constantine Alexander's blog

Partnership installs new ocean observation sensor to benefit abalone industry

A new network of water sensors in Monterey Bay is now aiding the abalone industry by monitoring water quality for harmful algal blooms and other potential hazards, helping to keep the valuable shellfish safe to eat while increasing knowledge of the bay’s environment.

The sensors monitor dissolved oxygen, ocean acidification levels, and oceanographic conditions that can lead to harmful algal blooms, among other hazards. The measurements will also create long, continuous records of the oceanographic environment in Monterey, feeding into the larger U.S. Integrated Ocean Observing System (IOOS®). This will also benefit other fisheries in the area and informs human health decisions.       

The Central and Northern California Ocean Observing System (CeNCOOS), a regional member of the NOAA-led U.S. IOOS program, is partnering with Moss Landing Marine Laboratories and the Monterey Abalone Company to install, operate, and maintain the water quality sensors in Monterey Bay. The system became operational in mid-June.

“This is about lives and livelihoods and is as much about keeping the food we eat safe as it is about the economy,” said Zdenka Willis, IOOS® program director. “Knowing what is in the water is critical to the fishing and aquaculture industries, especially in areas like Monterey Bay, which can be susceptible to harmful algal blooms.”

“Harmful algal blooms are suspected as the culprit in a recent abalone mortality event off the northern California coast, resulting in significant impacts to shellfish populations and other marine life,” said Dr. Leslie Rosenfeld, CeNCOOS executive director. “California’s farmed abalone industry produced more than 550,000 pounds of abalone worth approximately $9 million in 2008. This new station will help abalone growers monitor ocean conditions that can affect abalone health and take appropriate actions to safeguard their crops.”

NOAA supported CeNCOOS paid for the instrumentation, while Monterey Abalone Company and Moss Landing Marine Laboratories will maintain the station and share the data collected using the CeNCOOS public website. Crews installed the new sensor at the Monterey Abalone Company facility at the Monterey commercial wharf.

IOOS is a federal, regional, and private-sector partnership led by NOAA, which works to enhance the  ability to collect, deliver and use ocean information. IOOS delivers the data and information needed to increase understanding of our oceans and coasts, so that decision-makers can act to improve safety, enhance the economy, and protect our environment

NOAA’s mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage our coastal and marine resources. Join the NOAA on Facebook and/or Twitter.

 

Preserving ‘natural quiet’ the easy way

A recent study presents a cost and time-effective way to identify areas with particularly low levels of noise pollution. The recommended method will make it easier for EU Member States to recognise quiet areas which could offer great health and ecological benefits, as well as meeting one of the Environmental Noise Directive requirements.

More than 30% of the European population experiences noise levels that disrupt sleep or speech, and 20% are regularly exposed to noise levels that scientists consider an unacceptable health risk. To reduce noise exposure and preserve the high biodiversity that naturally quiet areas offer, the EU Environmental Noise Directive (END) requires Member States to identify and preserve areas that currently experience very low levels of noise from human influences, known as Quiet Areas (QAs). However, very few Member States have done so effectively because measuring how sound varies in time and space is technically very difficult.

The new study, co-funded by Greece and the European Union under the European Social Fund (ESF), identified open country QAs in Greece based on the distance from various sources of human-made noise, including road traffic, railway noise, residential areas, industrial noise, aircraft noise, ports, construction sites and sport/leisure facilities. To do this, each source of noise in Greece was located using the Corine Land Cover Database 2000 (CLC2000) and the researchers calculated how far the noise was expected to travel. When all the noise sources were mapped, areas of land over 10 km² that did not fall within the range of any source of noise were identified as potential QAs.

Using this method, the researchers identified 765 potential QAs in Greece, covering 65,126km² or nearly 48% of the country. In 24 out of the 51 prefectures that make up Greece, less than 50% of the territory was identified as a potential QA. Only two prefectures had QA coverage of over 70%. In the most populated areas of Greece, Attiki and Thessaloniki, QAs covered less than 20% of the land. Most QAs in the country contained either agricultural land (738 out of 765) or forest semi-natural areas (705 out of 765). Wetlands and water bodies featured in relatively few QAs (69 and 97, respectively), since the surrounding areas are often used extensively by humans.

Among agricultural QAs, the largest percentage of land was classified according to the CLC2000 database as ‘principally occupied by agriculture with significant areas of natural vegetation’ (10.9%). A further 7.5% was classified as ‘non-irrigated arable land’. Among the forest semi-natural QAs, sclerophyllous vegetation was the most common (20%), followed by broad-leaved forests (12.6%), transitional woodland scrub (12.2%) and natural grassland (11.3%).

The results suggested that QAs tend to be clustered together, rather than distributed randomly, and that they can be found at all altitudes from 0-2800 metres, with around half (48.5%) at medium altitudes. The spatial overlap of QAs with protected areas indicated that the high biodiversity, but also, recreational value of these areas could contribute to the Convention of Biological Conservation’s requests towards achieving the 2020 Aichi biodiversity targets. Distance-based measurements are not as accurate as true measurements of noise levels, which the European Commission recommends Member States to implement through END’s guidelines. However, detailed noise data over large geographical areas are not yet available in Greece, and the cost of doing so could be prohibitive.

This distance-based method could be a first step towards identifying QAs in Greece and other Member States, since it can be carried out quickly, over large areas and by non-experts. To see how reliable the method is, the noise levels in the identified QAs now need to be checked against ground truth data (data collected from cartography, meteorology, analysis of aerial photographs, satellite imagery or other remote sensing techniques) on noise measurements in the field, say the researchers.

Source: Votsi, N.E.P., Drakou, E.G., Mazaris, A.D., Kallimanis, A.S., Pantis, J.D. (2012). Distance-based assessment of open country Quiet Areas in Greece. Landscape and Urban Planning. 104; 279-288. DOI: 10.1016/j.landurbplan.2011.11.004.

Contact: nvotsi@bio.auth.gr or aressurreicao@uac.pt

Reducing roadkill: driver awareness needs improving

Wild animals are more likely to be hit by vehicles during times when roads have poorer surface conditions and during periods of low light, according to a study of moose in Sweden. The researchers emphasise that it is not possible to accurately predict hotspots for wildlife collisions using data on the movement of the animals alone, and suggest that efforts to reduce accidents should focus on driver awareness and road conditions.

The frequency of vehicle collisions with wildlife is expected to rise as road networks and traffic volumes increase, with negative impacts for biodiversity. The identification of collision ‘hotspots’ can help conservation managers develop strategies that reduce the risk of vehicles hitting wildlife. Previous efforts to pinpoint high risk zones have tended to focus on either data about actual accidents, or data on animal movement, but this study, part-funded by the EU¹, emphasises that both sets of data can help to accurately predict hotspots.

The researchers reached this conclusion by comparing data on the movement of moose with police data on traffic accidents with moose in northern Sweden. They found that collisions were not necessarily most likely to occur on roads that experienced higher levels of animal crossings, and identified several other factors at play. A total of 102 female moose in the rural Provinces of Västerbotten and Norrbotten were fitted with GPS collars, and their movements were tracked over a two and half year period. From this GPS data, the researchers calculated how many times the moose crossed roads, where and when, to try and predict high risk times and locations for collisions. As may be expected, the number of crossings increased during migration periods, peaking in May, June, and between November and January.

By law, moose-vehicle collisions in Sweden have to be reported to the police, and are typically reported by local hunters who take care of the injured or dead animal. When the researchers assessed police data representing 1158 incidents over a two year period, and compared them with the movement data, they saw that accident rates did not necessarily correspond with the busy migration periods. Collisions were most likely to occur between the months of October and January, and during the hours of 16.00-20.00, i.e. during periods of low light.

They also deduced from the police data that collision risk is greater where traffic speed is higher and in areas close to human settlement. The collision risk was lower on forest roads. While this may be partly because there is more traffic in more developed areas, it may also reflect driver awareness; drivers are less likely to expect to see moose in built up areas.

Combining accident data with animal movement data proves useful in predicting collision hotspots, says the study, as animal movement data do not provide a full picture of risk, but indicate movement corridors, and while police accident data tend to provide a fairly accurate time of collision, the accuracy of the accident location varies considerably.

Based on its findings, the study suggests that measures to reduce accidents with animals should focus on increasing driver alertness during certain times of the year, perhaps through a warning system, and in locations along animal migratory routes.

1. This project was partly funded by the EU Interregional IIIA project Moose in Mid-Scandinavia.

Source: Wiebke, N., Ericsson, G., Dettki, H. et al (2012) Difference in spatiotemporal patterns of wildlife road-crossings and wildlife-vehicle collisions. Biological Conservation.145(1): 70-78. DOI: 10.1016/j.biocon.2011.10.011.

Contact: wiebke.neumann@slu.se

 

 

 

The qualities of an integrated biodiversity observation system

There is a recognised need for a more comprehensive system to observe, track and compare biodiversity across the world. Three years ago a global network was established to help reach this goal. It has identified the necessary characteristics for such an integrated system and possible ways in which integration can occur.

The need for more global and integrated biodiversity data is exemplified by the UN Convention on Biological Diversity, which set 21 sub-targets for reducing the rate of biodiversity loss by 2010. However, the information for many of the proposed indicators was unavailable at a global scale.

The Group on Earth Observations Biodiversity Observation Network (GEO BON), created in 2008, links up existing networks that observe biodiversity, including national biodiversity communities, nature conservation agencies, UN organisations and NGOs. It aims to help co-ordinate observations and harmonise methods.

GEO-BON already has an active programme of work and has identified a number of characteristics that are essential to a global biodiversity observation system. Firstly, the system should have the overarching goal of helping and protecting biodiversity alongside human wellbeing, and should be accessible to all potential users. It should be global in coverage, but with sufficient sensitivity at national and local scales, improve coverage in developing countries, which are currently inadequately represented. This more integrated system should also have comprehensive coverage of different groups of species; currently, about 1.9 million species have been scientifically described, but it is estimated that there are 5 to 30 million species in existence.

GEO-BON also suggest that the system should be cost-efficient, for example, there should be minimum duplication of observations. The data should be quality controlled with detailed information on the location and time of observation, and it should be sustained, i.e. collected continually over time.

The network GEO-BON has also identified several forms of integration that need to take place between existing observation systems. For example, it highlights the importance of linking biodiversity data across marine, freshwater and terrestrial realms. There should also be more linking between ecosystems and habitats to allow habitats to act as proxies (or substitutes) for observation of species, especially as habitats may be easier to monitor remotely through methods such as GIS (geographic information systems). GEO-BON also suggests biodiversity data should be more integrated with data that represents drivers of biodiversity change, such as climate and soil quality data.

Better integration is also needed between social and natural sciences to ensure the recognition of cultural and economic value of biodiversity, as well as ecological value. There should also be more links between data collected in situ, onsite, and data gathered through remote means, such as satellite observations. Lastly, more harmonisation is needed between national observation systems and those that have been independently developed with their own standards and language. This will need common data exchange standards and protocols.

To address these issues of integration, a ‘co-development’ process is needed that involves all stakeholders and considers their needs. GEO BON achieves this with the concept of ‘Essential Biodiversity Variables’ (EBVs).This consists of 24 indicators of biodiversity which will be developed through a series of workshops with key stakeholders.

Source: Scholes, R.J., Walters, M., Turak, E. et al. (2012) Building a global observing system for biodiverisity. Current Opinion in Environmental Sustainability. 4:139-146. Doi: 10.1016/j.cosust.2011.12.005.

Contact: bscholes@csir.co.za

Habitat mapping method could help restore biodiversity

A new method for mapping long-term changes in habitat over large areas and in fine detail has been developed, which could help inform conservation plans to restore biodiversity to previous states. In a UK case study, researchers have used it to demonstrate the dramatic effects of intensive agriculture and afforestation on rural habitats since the 1930s.

Driven by increased demand for food and growing populations, major changes in rural landscapes during the second half of the 20^th century, particularly in Western Europe, have had damaging effects on biodiversity. Intensive agriculture, afforestation for timber production and urbanisation have been shown to not only reduce available habitat for wildlife, but to also cut the links between habitats - the ‘ecological connectivity’ that allows species to spread and move around. Without these connections, there is a greater risk of extinction.

There is increasing interest in restoring habitats at a landscape and regional scale. This study, conducted under the EU SCALES project, presents a new method of mapping habitat change to assist these efforts. The researchers argue that mapping is an important first step in conservation planning, with implications for the EU’s Natura 2000 initiative, and that their approach is unique in that it can cover a large area of land, show small details and assess changes over a long period of time.

They demonstrated its use by applying it to Dorset, a county in the UK of over 2500km². The researchers combined historic maps and soil data from the 1930s, before the onset of intensive agriculture, and developed appropriate habitat classifications, such as ‘heathland’ and ‘managed grassland’. Referring to habitat types, instead of land use functions, makes it easier to compare maps produced at different times or using different methods.

The information was used to produce a digital map of Dorset in the 1930s, with a fine-scaled resolution of 25 x 25 metres. The map illustrated the range of habitat types across the district at the time, and presents what could be considered an ‘ideal’ situation for semi-natural habitats. These maps were then compared to a land cover map of Dorset, produced from satellite data, for the year 2000.

The maps revealed that the total area of semi-natural vegetation in Dorset fell by 74% over the 70 year period, considerably reducing the amount of quality habitat for wildlife. This was mainly the result of conversion to land for intensive agriculture, but afforestation also played a role by introducing conifer plantations for timber.

Furthermore, the connectivity between the remaining fragments of habitat had fallen considerably. Most grasslands in 2000 had almost zero connectivity with other habitats more than a few hundred metres away, when ‘connectivity’ is considered as the ability of seeds from one habitat patch to disperse and end up at another habitat patch of the same type.

The case study demonstrates the capacity of this mapping method, although its accuracy could be improved with better data; the researchers suggest that actual losses in habitat are likely to be even greater than the maps indicate. They propose a quantitative framework for conservation planning that uses high resolution maps, such as these, to help identify habitats for preservation and a target level of connectivity.

Source: Hooftman, D.A.P., Bullock, J.M. (2012) Mapping to inform conservation: A case study of changes in semi-natural habitats and their connectivity over 70 years. Biological Conservation. 145(1):30-38. DOI: 10.1016/j.biocon.2011.09.015.

Contact: dann1@ceh.ac.uk

Eutrophication led to fish extinctions in Alps

Nutrient pollution and resulting eutrophication has caused a rapid loss of whitefish species from lakes in the European Alps, according to a new genetic and ecological study that sheds light on how these fish became extinct in Swiss lakes. The researchers suggest that diversity loss among whitefish during the last century was related to environmental changes induced by eutrophication such as changes in oxygen levels and food composition in lakes.

Eutrophication is characterised by low levels of oxygen in fresh or seawater, caused by a build up of nutrients that leads to rapid growth of algae and microbial decomposition over and above a level that the ecosystem can support. The main pollutants involved are nitrogen and phosphorus, which come from agriculture, household waste and industry. In the EU, eutrophication is controlled under the Nitrates and Urban Wastewater Treatment Directives.

In the mid to late twentieth century, eutrophication was widespread in Swiss lakes. Low levels of oxygen at the bottom of eutrophicated lakes reduced the number of whitefish eggs surviving to hatching. Diversity among whitefish species has decreased substantially during that same time, with the number of different species present declining by more than a third on average across 17 Swiss lakes. The researchers wanted to find out whether this loss of diversity was associated with eutrophication.

Their results suggest that eutrophication was to blame for losses in whitefish diversity to a very large extent. Based on analyses of whitefish DNA and morphological characters from samples before, during, and after the eutrophication peak – centred around the 1970s – they show that eutrophication has altered the habitats of whitefish and driven extinctions through a process known as ‘speciation reversal’. Speciation reversal occurs when species that were previously distinct breed together, thus mixing their genes and losing the genetic and phenotypic differences that once made them unique.

According to the researchers, speciation reversal can be rapid, resulting in extinction of species over just a few generations. It may also be difficult to detect because historical DNA samples are rarely available, or may be of poor quality. The species reversal that occurred in Swiss lakes was probably related to eutrophication reducing oxygen levels at the bottom of lakes. This caused a loss of the spawning habitats of deep-spawning whitefish species. At the same time, eutrophication also caused changes in the plankton communities preyed on by whitefish. Together these changes relaxed the mechanisms that maintained differentiation between the species and some whitefish species were lost as a result of breeding with other species.

In the lakes of the Alpine foothills, whitefish are keystone species, meaning that other species in the same ecosystem likely depend on their continuing survival and diversity. The researchers therefore suggest that their loss has had wider impacts on the ecosystems in the lakes that they inhabit. The same may be true of many other species in areas affected by eutrophication. Awareness of these more complex effects of eutrophication may help to inform monitoring programmes and attempts to reduce the impact of nutrient pollution on aquatic ecosystems.

Source: Vonlanthen, P., Bittner, D., Hudson A.G., et al. (2012). Eutrophication causes speciation reversal in whitefish adaptive radiations. Nature. 482, 337-362. DOI: 10.1038/nature0824.

Contact: ole.seehausen@eawag.ch

Scientists urge new approaches to plant research

n a paper published this week in the journal Science, a Michigan State University professor and a colleague discuss why if humans are to survive as a species, we must turn more to plants for any number of valuable lessons

		In a paper published this week in Science, MSU professor Robert Last discusses the importance of plant research. Credit: G.L. Kohuth, MSU Media Communications

You'd be amazed at how much you can learn from a plant.

In a paper published this week in the journal Science, a Michigan State University professor and a colleague discuss why if humans are to survive as a species, we must turn more to plants for any number of valuable lessons.

"Metabolism of plants provides humans with fiber, fuel, food and therapeutics," said Robert Last, an MSU professor of biochemistry and molecular biology. "As the human population grows and nonrenewable energy sources diminish, we need to rely increasingly on plants and to increase the sustainability of agriculture."

However, Last and co-author Ron Milo of the Weizmann Institute of Science point out that despite decades of plant genetic engineering, there are relatively few types of commercial products originating from this body of work.

"This is in part because we do not understand enough about the vastly complex set of metabolic reactions that plants employ," Last said. "It's like designing and building a bridge armed only with satellite images of existing bridges."

The authors say that perhaps the best approach is to bring together a variety of disciplines – not just plant scientists – to study how plants operate.

They also suggest looking hard at what brought plants to the place they are today – evolution.

"We think that understanding design principles of plant metabolism will be aided by considering how hundreds of millions of years of evolution has led to well-conserved examples of metabolic pathways," Last said.

One of the amazing aspects of plant metabolism is this: It must continuously strike a balance between evolving to meet an ever-changing environment while maintaining the internal stability needed to carry on life as it knows it.

In addition, the authors point out that plants experiment with specialized (also called secondary) metabolism which can produce novel chemicals that are used to defend against pathogens and herbivores.

"Humans benefit from this 'arms race' because some of these compounds have important therapeutic properties," Last said. "Unfortunately, design principles are not so well studied in these rapidly evolving metabolic processes. Using new approaches, including considering optimality principles, will lead to advances in medicinal chemistry as well as creating more and healthier food."

Last is Barnett Rosenberg chair of Biochemistry and Molecular Biology and Plant Biology. Co-author Milo is a professor of plant sciences at Israel's Weizmann Institute of Science.

Contact: Tom Oswald
tom.oswald@cabs.msu.edu
517-432-0920
Michigan State University

New technique could reduce number of animals needed to test chemical safety

Image shows mature fish spheroid 8 days after plating. Image used courtesy of Springer

A new way of testing the safety of natural and synthetic chemicals has been developed by scientists with funding from the Biotechnology and Biological Sciences Research Council (BBSRC). Their research, published today in the journal Ecotoxicology, could reduce the number of fish needed to test the toxicity of a range of chemicals including pharmaceuticals and environmental pollutants.

The researchers, led by Professor Awadhesh Jha of Plymouth University, have managed to coax cells from the liver of a rainbow trout to form a ball-shaped structure called a spheroid in a petri dish. This ball of cells behaves much more like normal animal tissue than cells grown in traditional ways in the lab and so can give researchers a more accurate picture of how an animal's body would respond to a chemical in the environment.

Fish are used to test whether both new and existing chemicals like pharmaceuticals can damage wildlife or the environment. Because a large number of spheroids can be produced from a single fish the use of this technique could mean less fish are needed to do these tests.

Professor Jha explains "This is a real breakthrough in our efforts to reduce the numbers of fish needed for toxicology testing. It is very important for the health of people, wildlife and whole ecosystems that we understand the effect of chemicals, both natural and manmade, in the environment, but we must strive to avoid the use of animals wherever possible."

One of the most impressive aspects of the fish spheroids is that they can be maintained in the lab for over a month. Many environmental pollutants cause health problems because they accumulate over time and become more concentrated further up the food chain. Because the fish spheroids can be maintained for longer time periods than normal cell cultures scientists can test the effect of long-term exposure to a potential toxin.

The fish spheroids were produced by a BBSRC-funded CASE student, Matthew Baron, who is being supervised by Professor Jha and his colleagues at Plymouth and AstraZeneca Safety Health and Environment. At present, scientists can use flat layers of fish cells to replace some live animal tests but these break down quickly and do not behave like real tissues. Spheroids are already well established models for testing on mammalian cells but this is the first time that they have been developed from fish cells.

Because the liver filters blood it is often the main organ where potential environmental toxins accumulate and are broken down by the body and so is the most important organ for testing toxicity. The researchers also hope to produce spheroids from fish gill cells, as the gills are another important site of toxin accumulation. By combining these two types of spheroids in a single system the researchers hope to develop a 'virtual fish' which could give a clear picture of how a particular chemical would affect a live animal.

Professor Douglas Kell, BBSRC Chief Executive said "Everyone wants to see fewer animals used in testing so this is great news. The UK has always led the way in efforts to reduce, refine and replace the use of animals in research. Whilst the use of some animals will remain important to ensuring that the medicines and other chemicals are safe to use and won't damage the environment, we are making great strides in the combining of new laboratory techniques and computer modelling to avoid using animals wherever possible."

Reference: "Towards a more representative in vitro method for fish ecotoxicology: morphological and biochemical characterisation of three-dimensional spheroidal hepatocytes" by Matthew G. Baron, Wendy M. Purcell, Simon K. Jackson, Stewart F. Owen and Awadhesh N. Jha

Contact: Mike Davies
mike.davies@bbsrc.ac.uk
44-179-341-4694
Biotechnology and Biological Sciences Research Council

Britain's urban rivers bounce back

Urban rivers throughout England and Wales have improved dramatically in water quality and wildlife over the last 20 years

Urban rivers throughout England and Wales have improved dramatically in water quality and wildlife over the last 20 years.

That's the conclusion of one the largest studies of national trends in river health ever undertaken.

After decades of pollution, typically from poorly treated sewage and industrial waste, rivers in or near Britain's major urban areas are regaining insects such as mayflies and stoneflies that are typical of fast-flowing, oxygen-rich waters. The range of invertebrates found has also increased, on average, by around 20%.

Researchers from Cardiff University's School of Biosciences carried out an independent analysis of data supplied by the Environment Agency using almost 50,000 samples from thousands of rural and urban locations.

The team puts the general improvement down to industrial decline, tighter regulation and improved wastewater treatment over recent decades.

The recovery has not been universal, however. Rivers in some rural upland areas – such as Wales and parts of northern England – appeared to deteriorate slightly. The team is now investigating these trends further.

Another important finding was that drought years reversed the recovery – at least temporarily.

Dr Ian Vaughan, lead author of the study said: "These important results show how benefits to river biodiversity – the huge array of species that live in our rivers – have arisen from investment and long-term restoration intended largely for other 'river ecosystem services' such as drinking water and sanitation."

Co-author, Professor Steve Ormerod, added: "While some pollutants are still problematic, there is no doubt that this is a major success story that shows what can be achieved by effective environmental regulation. These are very large improvements not only for river ecosystems, but for the many people who live, work and play along their banks everywhere from Burnley to the Black Country or from Merthyr Tydfil to Cardiff."

Head of Catchment Management at the Environment Agency, David Baxter, said: "High quality environments promote wellbeing and creativity, so improvements in rivers are important for wildlife, people and the economy. It is great to see this independent analysis confirm that urban rivers are recovering, but there is still more work to do. We're working with farmers, businesses and water companies to reduce pollution and improve water quality and we have plans to transform more than 9,500 miles of rivers in England and Wales by 2015."

A paper describing the study appears in the current issues of the prestigious international journal, Global Change Biology.

Contact: Steve Ormerod
Ormerod@cardiff.ac.uk
44-292-087-5871
Cardiff University

 

U Alberta resets date of earliest animal life by 30 million years

University of Alberta researchers have uncovered physical proof that animals existed 585 million years ago, 30 million years earlier than all previous established records show.

The discovery was made U of A geologists Ernesto Pecoits and Natalie Aubet in Uruguay. They found fossilized tracks of a centimetre long, slug-like animal left behind 585 million years ago in a silty sediment.

Along with other U of A researchers, the team determined that the tracks were made by a primitive animal called a bilaterian, which is distinguished from other non-animal, simple life forms by its symmetry-its topside is distinguishable from its bottom side-and a unique set of 'footprints'.

The researchers say the fossilized tracks indicate the soft-bodied animal's musculature enabled it to move through the sediment on the shallow ocean floor. The pattern of movement indicates an evolutionary adaptation to search for food, which would have been organic material in the sediment.

The precise age of the tracks was calculated at the U of A by dating the age of an igneous rock that intruded into the siltstone in the area where the tracks were found. It took more than two years for U of A researchers to satisfy themselves and a panel of peer review scientists that the age of 585 million years is accurate. The dating process included a trip back to Uruguay to collect more samples of the fossilized rock and multiple sessions of mass spectrometry analysis.

U of A paleontologist Murray Gingras said when it comes to soft-bodied animals and their tracks it's not unusual for the animal's body to disappear but its tracks become fossilized.

Prior to the U of A find and age confirmation, the oldest sign of animal life was dated at 555 million years ago from a find made in Russia.

Kurt Konhauser, a U of A geomicrobiologist, says the team's discovery will prompt new questions not only about the timing of animal evolution, but also the environmental conditions under which they evolved. Konhauser explains that the challenge now is "to find out how these animals evolved to the point where they were able to move about and hunt for food."

The U of A's research team includes Ernesto Pecoits, Natalie Aubet, Kurt Konhauser, Larry Heaman, and Richard Stern and Murray Gingras. The research was published June 28, in the journal Science.

Contact: Brian Murphy
brian.murphy@ualberta.ca
780-492-6041
University of Alberta