̽��ֱ�� of Cambridge - Memorial ̽��ֱ�� of Newfoundland

Why life on Earth first got big

sc604 — Mon, 25 Jun 2018 14:52:12 +0000

̽��ֱ��research, led by the ̽��ֱ�� of Cambridge, found that the most successful organisms living in the oceans more than half a billion years ago were the ones that were able to ‘throw’ their offspring the farthest, thereby colonising their surroundings. ̽��ֱ��results are reported in the journal Nature Ecology and Evolution.

Prior to the Ediacaran period, between 635 and 541 million years ago, life forms were microscopic in size, but during the Ediacaran, large, complex organisms first appeared, some of which – such as a type of organism known as rangeomorphs – grew as tall as two metres. These organisms were some of the first complex organisms on Earth, and although they look like ferns, they may have been some of the first animals to exist – although it’s difficult for scientists to be entirely sure. Ediacaran organisms do not appear to have mouths, organs or means of moving, so they are thought to have absorbed nutrients from the water around them.

As Ediacaran organisms got taller, their body shapes diversified, and some developed stem-like structures to support their height.

In modern environments, such as forests, there is intense competition between organisms for resources such as light, so taller trees and plants have an obvious advantage over their shorter neighbours. “We wanted to know whether there were similar drivers for organisms during the Ediacaran period,” said Dr Emily Mitchell of Cambridge’s Department of Earth Sciences, the paper’s lead author. “Did life on Earth get big as a result of competition?”

Mitchell and her co-author Dr Charlotte Kenchington from Memorial ̽��ֱ�� of Newfoundland in Canada examined fossils from Mistaken Point in south-eastern Newfoundland, one of the richest sites of Ediacaran fossils in the world.

Earlier research hypothesised that increased size was driven by the competition for nutrients at different water depths. However, the current work shows that the Ediacaran oceans were more like an all-you-can-eat buffet.

“ ̽��ֱ��oceans at the time were very rich in nutrients, so there wasn’t much competition for resources, and predators did not yet exist,” said Mitchell, who is a Henslow Research Fellow at Murray Edwards College. “So there must have been another reason why life forms got so big during this period.”

Since Ediacaran organisms were not mobile and were preserved where they lived, it’s possible to analyse whole populations from the fossil record. Using spatial analysis techniques, Mitchell and Kenchington found that there was no correlation between height and competition for food. Different types of organisms did not occupy different parts of the water column to avoid competing for resources – a process known as tiering.

“If they were competing for food, then we would expect to find that the organisms with stems were highly tiered,” said Kenchington. “But we found the opposite: the organisms without stems were actually more tiered than those with stems, so the stems probably served another function.”

According to the researchers, one likely function of stems would be to enable the greater dispersion of offspring, which rangeomorphs produced by expelling small propagules. ̽��ֱ��tallest organisms were surrounded by the largest clusters of offspring, suggesting that the benefit of height was not more food, but a greater chance of colonising an area.

“While taller organisms would have been in faster-flowing water, the lack of tiering within these communities shows that their height didn’t give them any distinct advantages in terms of nutrient uptake,” said Mitchell. “Instead, reproduction appears to have been the main reason that life on Earth got big when it did.”

Despite their success, rangeomorphs and other Ediacaran organisms disappeared at the beginning of the Cambrian period about 540 million years ago, a period of rapid evolutionary development when most major animal groups first appear in the fossil record.

̽��ֱ��research was funded by the Natural Environment Research Council, the Cambridge Philosophical Society, Murray Edwards College and Newnham College, Cambridge.

Reference
Emily G. Mitchell and Charlotte G. Kenchington. ‘ ̽��ֱ��utility of height for the Ediacaran organisms of Mistaken Point.’ Nature Ecology and Evolution (2018). DOI: 10.1038/s41559-018-0591-6

Inset image:
A close-up view of the Mistaken Point ‘E’ surface community. Credit: Emily Mitchell.

Some of the earliest complex organisms on Earth – possibly some of the earliest animals to exist – got big not to compete for food, but to spread their offspring as far as possible.

Reproduction appears to have been the main reason that life on Earth got big when it did.

Emily Mitchell

CG Kenchington

Artist’s reconstruction of the community at Lower Mistaken Point

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Opinion: We need to break science out of its ivory tower – here's one way to do this

Anonymous — Wed, 26 Apr 2017 10:52:33 +0000

Without hardware, there is no science. From Hooke’s microscope to the Hubble telescope, instruments are modern science’s platforms for producing knowledge. But limited access to scientific tools impedes the progress and reach of science by restricting the type of people who can participate in research, favouring those who have access to well-resourced laboratories in industrial or academic institutions.

Scientists in developing countries, grassroots community organisations, and citizen scientists can struggle to obtain and maintain the equipment they require to answer their own research questions.

̽��ֱ��result of this exclusion from participation is that scientific research becomes ever more elitist as a small number of people decide what the worthwhile and valid projects are. For example, the relative neglect of many tropical diseases and agricultural research on African subsistence crops demonstrates that local concerns in areas with limited scientific resources are often not sufficiently addressed by global science.

Likewise, public concerns and desire for transparency around technology can also be ignored. Research on fracking has received $137 million from the United States Department of Energy. But despite vocal concerns about water pollution, no affordable technologies have been developed for communities to use to monitor their own air or water, even though access to the relevant data from industry is difficult. Locking science inside ivory and industry towers restricts what it can look like.

Open hardware

̽��ֱ��open science hardware movement challenges these norms with the goal of providing different futures for science, using hardware as a launching point. It argues that plans, protocols and material lists for scientific instruments should be shared, accessible and able to be replicated. ̽��ֱ��fact that a lot of modern scientific equipment is a consumer product that is patented, not supplied with full design information and difficult to repair also blocks creativity and customisation.

For example, open source project Oceanography for Everyone recently crowdfunded an open conductivity, temperature and depth (CTD) instrument out of frustration with the lack of low-cost instrumentation available. CTD instruments are the workhorses of oceanography research, and usually cost thousands of dollars. Oceanography for Everyone’s model achieves comparable data but costs US$300 to build, and the plans are public on GitHub. Think of OpenCTD like a really nice shirt. You could buy one for $40, or if you don’t have enough money but you do have a sewing pattern and some time, you could purchase the fabric for $5 and make it yourself, and even customise it to your needs and tastes.

Lower cost is only one goal of open science hardware. CERN, the European Particle Physics Laboratory in Geneva, pioneered an Open Hardware License to enable large-scale, open collaboration on projects. One of these, White Rabbit, is an electronic controller for precise synchronisation of signals across vast distances. White Rabbit ensures that some of the world’s largest particle accelerators are coordinated. But it’s also freely available to anyone, and has found new uses in designing smart electricity grids.

Members of CLEAR using hand tools to repair an open science hardware trawl (LADI trawl) for monitoring marine plastics. MEOPAR

Equality or equity?

Instruments such as OpenCTD and White Rabbit are built on the premise of equality, the idea that everyone should have access to scientific tools. Yet the ability to access such tools is only half the story: it doesn’t address the acute disparities in who is creating science in the first place. And these are enormous. In 2015, ̽��ֱ��Guardian reported that Africa produces just 1.1% of global scientific knowledge. And recent data from UNESCO indicates that only 28% of researchers globally are women. Women do not represent 50% of scientists in a single country in the world.

Attempting to address this problem, several feminist laboratories create and use open science hardware. For example, the Civic Laboratory for Environmental Action Research (CLEAR) is a feminist marine pollution lab in Newfoundland, Canada. And the GynePunks are a group of bio-hackers at the forefront of DIY gynaecology, based in Barcelona.

These labs are not merely bringing more women and trans scientist-inventors into science-as-usual. They prioritise equity rather than equality, recognising that when people start from fundamentally different social, economic, educational and political positions, treating everyone the same does not overcome those differences. In doing so, they transform science in terms of how research priorities are chosen and articulated, what kinds of knowledge is considered valid, and, of course, how scientific tools are made and distributed.

Equality vs. Equity. Interaction Institute for Social Change. Artist: Angus Maguire. CC BY 2.0

Beyond the lab

Particularly valuable work is being done by groups attempting to move science out of the lab and into places and frameworks where it would not usually occur.

For example, Public Lab is a US-based environmental science community founded by frustrated citizens on the Gulf Coast following the Deepwater Horizon oil disaster in 2010. Getting accurate, timely and public high resolution data about local damage was impossible due to flight restrictions over the spill area and satellites are too far away to provide the same level of detail. So citizen scientists stitched together photos from cheap cameras suspended from helium balloons. ̽��ֱ��tools are open and accessible, and the research is done by and for local people without science degrees.

Public Lab volunteers mapping the Deep Horizon oil spill using a low-cost weather balloon setup that is openly documented on the Public Lab wiki. Jeff Warren/Flickr

Likewise, the work of Lifepatch, an Indonesian citizen initiative in art, science, and technology which uses low-cost methods and open tools such as webcam microscopes, is deeply rooted in Indonesian collective culture. ̽��ֱ��questions of basic, daily life and everyday needs have driven projects with local communities on river water quality, bio-recovery of soils altered by volcanic eruptions and safe fermentation practices in collaboration with local academics.

All of these projects demonstrate the value of science grounded in specific places, complex local traditions, ethics, contexts and research questions, rather than a universal science that works the same everywhere for everyone. We need to push science towards communal, bottom-up, and collaborative practices; away from territorial, proprietary, institutional, Western-dominated and individualistic practices.

This has significant implications for where science happens, who is involved, and as a result, the types of knowledge that can be produced. Open science hardware is about creating new futures for science.

Max Liboiron, Professor of Geography and Environmental Science, Memorial ̽��ֱ�� of Newfoundland and Jenny Molloy, Coordinator, Synthetic Biology Strategic Research Initiative, ̽��ֱ�� of Cambridge

This article was originally published on ̽��ֱ��Conversation. Read the original article.

Science doesn't work the same for everyone everywhere - there are huge disparities in access to scientific hardware, and in gender and minority representation in labs. In this piece from ̽��ֱ��Conversation, Jenny Molloy (Department of Earth Sciences) and Max Liboiron (Memorial ̽��ֱ�� of Newfoundland) look at some of the initiatives around the world which are attempting to level the playing field for scientists.

US Food and Drug Administration

Stem Cell Research

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

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Animals first flex their muscles

sc604 — Wed, 27 Aug 2014 07:15:00 +0000

An unusual new fossil discovery of one of the earliest animals on earth may also provide the oldest evidence of muscle tissue – the bundles of cells that make movement in animals possible.

̽��ֱ��fossil, dating from 560 million years ago, was discovered in Newfoundland, Canada. On the basis of its four-fold symmetry, morphological characteristics, and what appear to be some of the earliest impressions of muscular tissue, researchers from the ̽��ֱ�� of Cambridge, in collaboration with the ̽��ֱ�� of Oxford and the Memorial ̽��ֱ�� of Newfoundland, have interpreted it as a cnidarian: the group which contains modern animals such as corals, sea anemones and jellyfish. ̽��ֱ��results are published today (27 August) in the journal Proceedings of the Royal Society B.

Historically, the origin, evolution and spread of animals has been viewed as having begun during the Cambrian Explosion, a period of rapid evolutionary development starting 541 million years ago when most major animal groups first appear in the fossil record.

“However, in recent decades, discoveries of preserved trackways and chemical evidence in older rocks, as well as molecular comparisons, have indirectly suggested that animals may have a much earlier origin than previously thought,” said Dr Alex Liu of Cambridge’s Department of Earth Sciences, lead author of the paper.

“ ̽��ֱ��problem is that although animals are now widely expected to have been present before the Cambrian Explosion, very few of the fossils found in older rocks possess features that can be used to convincingly identify them as animals,” said Liu. “Instead, we study aspects of their ecology, feeding or reproduction, in order to understand what they might have been.”

̽��ֱ��new fossil, named Haootia quadriformis, dates from the Ediacaran Period, an interval spanning 635 to 541 million years ago. It differs from any previously described Ediacaran fossil, as it comprises of bundles of fibres in a broadly four-fold symmetrical arrangement: a body plan that is similar to that seen in modern cnidarians.

̽��ֱ��researchers determined that the similarities between Haootia quadriformis and both living and fossil cnidarians suggest that the organism was probably a cnidarian, and that the bundles represent muscular tissue. This would make it not only a rare example of an Ediacaran animal, but also one of the oldest fossils to show evidence of muscle anywhere in the world.

“ ̽��ֱ��evolution of muscular animals, in possession of muscle tissues that enabled them to precisely control their movements, paved the way for the exploration of a vast range of feeding strategies, environments, and ecological niches, allowing animals to become the dominant force in global ecosystems,” said Liu.

̽��ֱ��research was funded by the Natural Environment Research Council, the Natural Sciences and Engineering Research Council of Canada, the Burdett Coutts Fund of the ̽��ֱ�� of Oxford, and the National Geographic Global Exploration Fund Northern Europe.

Inset image: Artist reconstruction of Haootia quadriformis. Credit: Martin Brasier

A new fossil discovery identifies the earliest evidence for animals with muscles.

Animals may have a much earlier origin than previously thought

Alex Liu

Alex Liu/Jack Matthews

Fossil of Haootia quadriformis

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