Tag Archives: Cambridge University

Archaeologists discover Bronze Age “British Pompeii”

Archaeologists have discovered something as valuable as the Roman Pompeii – a Bronze Age settlement that contains the “best-preserved Bronze Age dwellings ever found” in the country. Pots with meals still inside have been found at the site.

Cambridge Archaeological Unit

Archaeologists from Cambridge University have been working at the Cambridgeshire site, beneath the Must Farm quarry, since September, and by now they have a pretty good idea of what happened there. The settlement consisted of circular wooden houses that housed an extended family of around 10 people. The houses were built on stilts above water, and when a fire started to spread and destroyed the stilts, the houses collapsed into the river, where muddy sediments helped to preserve them very well.

Sadly, just like Pompeii, a disaster seems to be the key for the good preservation. Duncan Wilson, chief executive of Historic England, which is funding the project, said:

“A dramatic fire 3,000 years ago combined with subsequent waterlogged preservation has left to us a frozen moment in time, which gives us a graphic picture of life in the Bronze Age.”

Cambridge Archaeological Unit

The Bronze Age in Britain kicked in approximately 2500 BC and lasted up until 800-650 BC, ending when migratory people brought in iron from overseas. These huts date from 1000-800 BC, towards the end of the Bronze Age and could help us better understand how people lived back then.

“We are learning more about the food our ancestors ate, and the pottery they used to cook and serve it. We can also get an idea of how different rooms were used,” Wilson said, adding that the importance of this finding is global and not regional. “This site is of international significance and its excavation really will transform our understanding of the period.”

So far, aside from the houses, archaeologists have found pots and pans of varying sizes, spears and daggers, exotic glass beads and even textiles that had been fashioned from tree bark. The textiles seem to have been created from lime tree bark. Digs have also uncovered  “exotic” glass beads that formed part of a necklace which hints “at a sophistication not usually associated with the Bronze Age”.

These glass beads are thought to have formed a necklace. Cambridge Archaeological Unit

David Gibson, from Cambridge Archaeological Unit, which is leading the excavation, said:

“So much has been preserved, we can actually see everyday life during the Bronze Age in the round. It’s prehistoric archaeology in 3D, with an unsurpassed finds assemblage both in terms of range and quantity.”

Most other sites don’t even begin to compare with it.

“Most don’t have any timber remaining, just post-holes and marks where posts would have been,” he said. “So far this is unique as we have the roof structure as well.”

Work must be carried on as fast as possible at the site, because there are concerns that water levels will rise in late winter and spring and could wash away some of the artifacts and structures.

Artist illustration of Hallucigenia sparsa based on recent electron scan microscope images. Credit: Danielle Dufault

Hallucigenia: the half-billion years old freaky ancestor of molting animals

When the freakish Hallucigenia was first discovered in the 1970s, paleontologists found it nearly impossible to distinguish head from tail. Now, the bizarre creature – an ancestor to molding animals like crabs, worms or krill – had its features identified with unprecedented precision, but that doesn’t mean it’s less freakish looking: worm-like with a mouth adorned with a ring of teeth, bearing seven pairs of legs ending in claws, and three pairs of tentacles along its neck. To finish it off, its back was covered with enormous spikes. Yes, it looks weird, but so were most animals that lived 500 million years ago during the so-called Cambrian explosion – a period of massive bloom in terms of diversity of life and evolution. Most creatures of those times were somewhat primitive, but remarkably, Hallucigenia was quite advanced for its age.

Artist illustration of Hallucigenia sparsa based on recent electron scan microscope images.  Credit: Danielle Dufault

Artist illustration of Hallucigenia sparsa based on recent electron scan microscope images. Credit: Danielle Dufault

The fossil remains first discovered in Canada’s Burgess Shale are highly difficult to interpret. Basically, if you look at it in 2D it all looks like a worm with legs or spikes – hard to tell which is which. It’s no wonder that scientists initially described the creature totally upside down: the spines on the back were thought to be legs and vice-versa, and the head was mistaken for a tail. Using electron scan microscopy, researchers at University of Cambridge, the Royal Ontario Museum and the University of Toronto imaged the ancient Hallucigenia with unprecedented precision, casting aside ambiguities.

“Prior to our study there was still some uncertainty as to which end of the animal represented the head, and which the tail,” saidDr Martin Smith, a postdoctoral researcher in Cambridge’s Department of Earth Sciences, and the paper’s lead author. “A large balloon-like orb at one end of the specimen was originally thought to be the head, but we can now demonstrate that this actually wasn’t part of the body at all, but a dark stain representing decay fluids or gut contents that oozed out as the animal was flattened during burial.”

After they realized which end is which, Smith was prompted to revisit the fossils and dig up the sediments around the head of the fossilized creature. This revealed some interesting clues related to its last moments alive. Apparently, this particular specimen was buried in a mudslide.

“This let us get the new images of the head,” said Caron. “When we put the fossils in the electron microscope, we were initially hoping that we might find eyes, and were astonished when we also found the teeth smiling back at us!”

Fossiled remains of Hallucigenia. Image: Jean-Bernard Caron

Fossiled remains of Hallucigenia. Image: Jean-Bernard Caron

Adorable and nightmarish-looking at the same time, Hallucigenia measured between 10 and 50 millimetres long and its head bore a simple pair of eyes and a row of needle-like teeth. The right of teeth likely helped the animal generate suction, flexing in and out, like a valve or a plunger, in order to suck its food into its throat, as reported in Nature.

“These teeth resemble those we see in many early moulting animals, suggesting that a tooth-lined throat was present in a common ancestor,” said Caron. “So where previously there was little reason to think that arthropod mouths had much in common with the mouths of animals such as penis worms, Hallucigenia tells us that arthropods and velvet worms did ancestrally have round-the-mouth plates and down-the-throat teeth – they just lost or simplified them later.”

Hallucigenia belongs to a group called ecdysozoans, which includes velvet worms (onychophorans) and water bears (tardigrades). While Hallucigenia isn’t the ancestor to all ecdysozoans, it is definitely high up the evolutionary tree and direct precursor to velvet worms. In fact, the findings helped the researchers assert that velvet worms initially had the same configuration, but lost it in time due to evolutionary mechanisms. Smith and Javier Ortega-Hernandez published a paper last year  that reported five key characteristics that link the species to the velvet worms.

“The early evolutionary history of this huge group is pretty much uncharted,” said Smith. “While we know that the animals in this group are united by the fact that they moult, we haven’t been able to find many physical characteristics that unite them.”

“It turns out that the ancestors of moulting animals were much more anatomically advanced than we ever could have imagined: ring-like, plate-bearing worms with an armoured throat and a mouth surrounded by spines,” said Dr Jean-Bernard Caron, Curator of Invertebrate Palaeontology at the Royal Ontario Museum and Associate Professor in the Departments of Earth Sciences and Ecology & Evolutionary Biology at the University of Toronto. “We previously thought that neither velvet worms nor their ancestors had teeth. But Hallucigenia tells us that actually, velvet worm ancestors had them, and living forms just lost their teeth over time.”

Biologists find algal embryo that “turned itself inside out”

Researchers from Cambridge have, for the first time, captured a 3D video of a living algal embryo turning itself inside out: from a sphere into a mushroom and into a sphere again. The results could help us better understand the process of gastrulation in animal embryos — which biologist Lewis Wolpert called “the most important event in your life.”

Biologists were studying the embryos of a green algae called Volvox, that forms spherical colonies of up to 50,000 cells. They live in a variety of freshwater habitats and interestingly, they demonstrated both individuality and working for the good of their colony, acting like one multicellular organism.

Using fluorescent microscopy, scientists were able to test a mathematical model of morphogenesis — the origin and development of an organism’s structure and form — and see how it behaves when it turns itself from a sphere to a mushroom shape and then back again.

Credit: Stephanie Höhn, Aurelia Honerkamp-Smith and Raymond E. Goldstein

The process is important not only for algae, but also for animals, as it is very similar to a process called gastrulation – a phase early in the embryonic development of most animals, during which the single-layered blastula is reorganized into a trilaminar (“three-layered”) structure known as the gastrula. Gastrulation is the result of complex cellular interactions, which makes it extremely difficult to quantify and understand in terms of raw numbers.

“Until now there was no quantitative mechanical understanding of whether those changes were sufficient to account for the observed embryo shapes, and existing studies by conventional microscopy were limited to two-dimensional sections and analyses of chemically fixed embryos, rendering comparisons with theory on the dynamics difficult,” said Professor Raymond E. Goldstein of the Department of Applied Mathematics and Theoretical Physics, who led the research.

Now is the first time scientists have been able to capture this process in 3D, which will also aid them in understanding gastrulation.

Volvox is a genus of chlorophytes, a type of green algae. Image via Wikipedia.

“It’s exciting to be able to finally visualise this intriguing process in 3D,” said Dr Stephanie Höhn, the paper’s lead author. “This simple organism may provide ground-breaking information to help us understand similar processes in many different types of animals.”

Journal Reference: Stephanie Höhn, Aurelia R. Honerkamp-Smith, Pierre A. Haas, Philipp Khuc Trong, and Raymond E. Goldstein. Phys. Rev. Lett. 114, 178101 – Published 27 April 2015 [Link]

 

Featured Researchers: This Week in Science

We talk a lot about science and research, but we don’t spend enough time talking about the people who actually do the research. In case you haven’t followed our previous feature, here is where we share some of the most interesting studies from the week, and share a bit of information about the scientists who made them.

One third of fracking chemicals are of unknown toxicity

Article
Featured Researcher: William Stringfellow
Affiliantion: Lawrence Berkeley National Laboratory
Research Interests: The major focus of his research is the study of environmental biokinetics (the study of movements of or within organisms).  In an open system, the state of the microbial community is determined by the physical and chemical conditions of the environment and is rarely, if ever, limited by availability of microorganisms. The microorganism will grow until the limiting condition is met, whether it is nutrient availability, energy supply, toxicity, or physical parameters such as available surface for attachment or washout conditions.

Scientists find how lizards regenerate their tails

Scientific Paper
Article
Featured Researcher: Kenro Kusumi
Affiliation: Arizona State University
Research Interests: Kenro Kusumi studies development, regeneration, evolution and diseases of the spine. His research team explores what genes shape the vertebral column, how certain vertebrates such as lizards can regenerate their tails, how evolution has produced a diversity of spinal morphology, and how the inactivation of specific genes can lead to spinal diseases such as congenital scoliosis. They approach these questions by examining how genome information shapes development and adult function.

This bacterium shoots wires out of its body to power itself

Article
Featured Researcher: Mohamed El-Naggar
Affiliation: University of Southern California
Research Interests: Moh El-Naggar is a pioneer in studying energy conversion and charge transmission at the interface between living cells and synthetic surfaces. His work, which has important implications for cell physiology, may lead to the development of new hybrid materials and renewable energy technologies that combine the exquisite biochemical control of nature with the synthetic building blocks of nanotechnology.

How loud music damages your hearing

Martine-Hamann

Article
Featured Researcher: Martine Hamann
Affiliation: University of Leicester
Research Interests: “We are studying cellular mechanisms underlying tinnitus, using a combination of electrophsysiological, morphological and behavioural studies.  We seek to understand how nerve cells memorize an auditory trauma (neuronal plasticity) and aim to find biomarkers for pathogenic processes related to hearing loss and tinnitus.”

Hallucigenia revealed: the most surreal creature from the Cambrian

Scientific Paper
Article
Featured Researcher: Martin Smith
Affiliation: Cambridge University
Research Interests: “I am interested in the origin and establishment of the modern animal groups. My work includes the study of unusual organisms from Burgess Shale-type deposits and their microscopic counterparts, the Small Carbonaceous Fossils. I also have an interest in the phylogenetic techniques used to identify the affinity of these organisms, and in the preservation of these remarkable fossils.”

One single scrap car battery could be turned into solar cells that power 30 homes

Scientific Paper
Article
Featured Researcher: Angela Belcher
Affiliation: Massachusetts Institute of Technology
Research Interests: “The focus of our research is understanding and using the process by which Nature makes materials in order to design new hybrid organic-inorganic materials. Our research is very interdisciplinary in nature and brings together the fields of inorganic chemistry, materials chemistry, biochemistry, molecular biology and electrical engineering.”

100,000 elephants killed in Africa between 2010 and 2012

Article
Featured Researcher: George Wittemyer (donate to help fund his research here)
Affiliation: Colorado State University
Research Interests: George Wittemyer has dedicated his scientific career to research that is helping to combat poachers and conserve one of Earth’s most noble species – elephants. Wittemyer’s research is helping inform policymakers and potential ivory consumers around the world about the detrimental impacts of the illegal ivory trade on the elephant species, and he hopes the information from his findings will help stem ivory demand and prevent the continued decline of elephant populations.

Eating less meat could be the solution to water use
Scientific Paper: Eating less meat could be the solution to water use
Article
Featured Researcher: Mika Jalava
Affiliation: Aalto University
Research Interests: I couldn’t find much info about Mika Jalava, but I have contacted her in the hope that she will tell us a bit about herself.

All images taken from the researchers’ page.

Hallucigenia revealed: the most surreal creature from the Cambrian

Artistic representation of Hallucigenia. Image via The Independent.

It looks like a painting from Salvador Dali – but Hallucigenia was very much real. Truly one of the most surreal creatures to ever walk the face of the planet, it was finally deciphered and understood (at least partially) by paleontologists, after 4 decades of study. The process discovered not only its position in the tree of life, but also its only surviving descendants.

Life on Earth was pretty dull until the Cambrian explosion, but it was never dull after it. The Cambrian is the time when most of the major groups of animals first appear in the fossil record. This event is sometimes called the “Cambrian Explosion,” because of the relatively short time over which this diversity of forms appears. It was a period of evolutionary experimentation; animals with complex body plans evolved walking, swimming, crawling and burrowing. Numerous diverse creatures appeared, including Anomalocaris (a 1 meter predator with moving lobes on the side of its body and 2 arm-like features next to its mouth), Diania (spiny animals with 10 pairs of legs) and the more famous trilobites. But even with this explosion of life, with this diversification to fill out every single niche out there, Hallucigenia still seems surreal. Believe it or not, paleontologists now believe that it is related to a small group of worm-like creatures with short legs that inhabit the underground of some tropical forests.

Anomalocaris. Image Source: The Cambrian Explosion: The Construction of Animal Biodiversity

Martin Smith and Javier Ortega-Hernandez of Cambridge University have detected key physical similarities between Hallucigenia and the so-called velvet worms, known more formally as the onychophorans – organisms with tiny eyes, antennae, multiple pairs of legs and slime glands. Their study, which was published in Nature, shows five key characteristics that link the species to the velvet worms.

A Hallucigenia fossil found in the Burgess shale. Image credits: Smithsonian.

In order to reach this conclusion they had to create high-magnification images of the fossils of Hallucigenia, which grew no longer than 3.5 cm. The first thing they found was the way the claws at the end of its limbs are arranged. Under an electron microscope, each claw has two or three successive layers of cuticle nestled one within the other, like the layered skins of an onion. Dr Smith said:

“We think this enabled them to grow a new set of claws before they shed their skins, which they had to do to grow. A very similar feature is found in the claws and jaws of the velvet worms, and no other animal shares this particular characteristic. It means that the animals do not have to wait for a new claw to form after shedding their skin to grow – they already have one ready formed,” he explained.

In fact, paleontologists have never been sure what is Hallucigenia’s front and what is its back – but this study clears that out too: the front has two or three pairs of appendages and the back has a rounded end where the gut probably terminates. They also showed that the fearsome spikes on Hallucigenia’s back were wrongly confused for legs, and were in fact a defense mechanism against the growing number of Cambrian predators.

For biologists and paleontologists, the Cambrian is probably the most interesting period of all geological history. It’s the period where life as we know it started to shape up. At one time in history, it was thought that life originated in the Cambrian, but now we know that in order to evolve, it has to evolve form something – and geologists have since found numerous evidence of pre-Cambrian life, most notably the Ediacaran fauna and the 3.5 billion years old stromatolites.

Dickinsonia costata, an iconic Ediacaran organism, displays the characteristic quilted appearance of Ediacaran enigmata. Image via Wiki Commons.

“It’s often thought that modern animal groups arose fully formed during the Cambrian explosion. But evolution is a gradual process,” said Martin Smith of Cambridge. “Today’s complex anatomies emerged step by step, one feature at a time. By deciphering ‘in-between’ fossils like Hallucigenia, we can determine how different animal groups built up their modern body plans,” he said.

 Journal Reference: Martin R. Smith, Javier Ortega-Hernández. Hallucigenia’s onychophoran-like claws and the case for Tactopoda. Nature, 2014; DOI: 10.1038/nature13576