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Science News

19 Posts tagged with the evolution tag
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Large centipedes and larger datasets

 

Dr Greg Edgecombe, Department of Earth Sciences, NHM

 

27th January - 4.00 pm

 

Earth Sciences Seminar Room (Basement, WEB 05, formerly Mineralogy Seminar Room)

                                         

Scolopendromorpha includes the largest and most fiercely predatory centipedes, totalling more than 700 species.  Subjected to phylogenetic analysis since the late 1990s, early studies drew on small sets of external morphological characters, mostly those used in classical taxonomic works.

 

NaturalHistoryMuseum_PictureLibrary_055195_preview.jpg

Scolopendra gigantea

 

In order to bolster the character sample, new anatomical data were worked up by systematically sampling the group’s diversity in order to formulate new characters from understudied structures/organ systems. Simultaneously, targeted sequencing of a few markers for a small (but growing) number of species provided the first molecular estimates of phylogeny.  These have resulted in stable higher-level relationships that predict a single origin of blindness in three lineages that share this trait, and are now backed up by transcriptomic datasets with high gene occupancy. Explicit matrices of morphological characters and fossils coded as terminal taxa remain vital to “total evidence” dating/tip dating of the tree.

 

More information on attending seminars at http://www.nhm.ac.uk/research-curation/news-events/seminars/

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Deep Diving, New Species Discovery and the Greatest Library on Earth

 

Special Science Seminar on communicating how biodiversity is the Earth's most valuable asset

 

Richard L. Pyle

Bishop Museum, Honolulu, Hawaii

   

Wednesday 14 January, 4pm Flett Theatre, NHM London

 

Preceded by coffee & tea in Flett Foyer from 3:15pm

    

The number of species on planet Earth that remain unknown to science exceeds (perhaps vastly) the number of species that have so far been discovered, let alone formally documented. Earth's biodiversity, which represents a library of accumulated information shaped by nearly four billion years of evolution, is arguably the most valuable asset on the planet for the long-term survival of humanity. Within the global biodiversity library, we are at this point in human history like toddlers running through the halls of the Library of Congress, largely unaware of the true value of the information that surrounds us. At the current pace of species discovery and documentation, in the context of what appears to be the dawn of the sixth great extinction, we are losing the race to document this enormous wealth of information before it is lost forever. Taxonomists are the librarians, developing new tools to build the card catalog for the Greatest Library on Earth. The tools include new research and means to access and integrate information. What we accomplish within the next twenty years will impact the quality of life for humans over the next twenty thousand years. 

 

Rich Pyle is globally recognised as an ichthyologist exploring extreme deep reef habitats, a bioinformatician and an ICZN Commissioner, a SCUBA re-breather engineer and and a two-time, two-topic TED Speaker. Here’s his TED blurb:

  • Ichthyologist Richard Pyle is a fish nerd. In his quest to discover and document new species of fish, he has also become a trailblazing exploratory diver and a pioneer of database technology.  A pioneer of the dive world, Richard Pyle discovers new biodiversity on the cliffs of coral reefs. He was among the first to use rebreather technology to explore depths between 200 and 500 feet, an area often called the "Twilight Zone." During his dives, he has identified and documented hundreds of new species. Author of scientific, technical and popular articles, his expeditions have also been featured in the IMAX film Coral Reef Adventure, the BBC series Pacific Abyss and many more. In 2005, he received the NOGI Award, the most prestigious distinction of the diving world.
  • Currently, he is continuing his research at the Bernice P. Bishop Museum, outside Honolulu, Hawai'i, and is affiliated with the museum's comprehensive Hawaii Biological Survey. He also serves on the Board of Directors for the Association for Marine Exploration, of which he is a founding member. He continues to explore the sea and spearhead re-breather technology, and is a major contributor to the Encyclopedia of Life.
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Prof. Mel Greaves FRS, Institute of Cancer Research

 

Friday 5 December 12 noon,  Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)

 

All cancers share the common feature of being clonal expansions of mutant cells that, over years or decades, disseminate within and between tissues, hijacking essential normal functions. But cancers differ widely in their tissue of origin, underlying mutational spectra, time frame of progression, pathological impact and clinical course. The systematics or classification of cancer subtypes therefore poses a considerable challenge with biologists, histopathologists and oncologists applying differing criteria.

 

Over recent years, a new conceptual framework has emerged that makes biological sense of all the diversity. This views cancer as a process of somatic cell evolution driven by mutational diversification and natural selection or adaptation within the specialised ecosystem habitats of the body. The implications of this new vision for diagnosis, prognostication and control of disease are very substantial.

 

More information on attending seminars at http://www.nhm.ac.uk/research-curation/news-events/seminars/

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Denis Michez,  University of Mons, Belgium

 

Wednesday 2 April 11:00

 

Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)

 

Bees (Anthophila) are one of the major groups of angiosperm-pollinating insects and accordingly are widely studied in both basic and applied research, for which it is essential to have a clear understanding of their phylogeny, and evolutionary history. Direct evidence of bee evolutionary history has been hindered by a dearth of available fossils needed to determine the timing and tempo of their diversification, as well as episodes of extinction.

NaturalHistoryMuseum_PictureLibrary_015744_Comp-1 bee.jpgCopal from East Africa containing Apis mellifera

 

Here we assess the similarity of the forewing shape of bee fossils with extant and fossil taxa using geometric morphometrics analyses. Predictive discriminant analyses show that fossils share similar diagnostic forewing shapes with families like Apidae, Halictidae, Andrenidae and Melittidae. Their taxonomic assessments provide new information on the distribution and timing of particular bee groups like corbiculate groups, most notably the extension into North America of possible Eocene-Oligocene cooling-induced extinctions.

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.htm

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Monotropa.jpg

 

Phylogenetics and evolution of some early and oddball plants

 

Sean Graham

University of British Columbia

 

Friday 8 November 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)


My research group works on multiple problematic nodes in the plant Tree of Life. Here I focus on two major subjects from phylogenetic and evolutionary perspectives: (1) The 'early' aquatic flowering-plant family Hydatellaceae; (2) the mycoheterotophic plants, which are diverse lineages of non-photosynthetic plants that rely on fungi for their carbon budget.

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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Coral.jpg

 

Conservation of reef corals of the world: why phylogeny matters


Danwei Huang

Postdoctoral scholar, University of Iowa

 

Friday 18 October 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)


One third of the world's reef-building corals are facing heightened extinction risk from anthropogenic climate change and local impacts. Extinction probabilities aside, species are not equal. Rather, evolutionary processes render each species, or species assemblage in general, unique with a distinctive history that can be characterised for conservation. My research is aimed at quantifying these patterns based on a robust understanding of the coral tree of life. In this talk, I will show that it is critical to consider species' contribution to evolutionary diversity in conjunction with their extinction risk when setting priorities to safeguard biodiversity.

 

My analyses identify the most endangered lineages that would not be given top priority on the basis of risk alone, and further demonstrate that corals susceptible to impacts such as bleaching and disease tend to be close relatives. One of Earth's most threatened reef regions, the Coral Triangle, is also famously the most biodiverse. While competing ideas are plentiful, the dynamics underlying this biogeographic pattern remain poorly understood. Phylogenetic modelling adds a valuable dimension to these explanations, and can help us uncover the evolutionary processes that have shaped coral richness in the hotspot. Indeed, conservation of the world's reef corals requires protecting the historical sources of diversity, particularly the evolutionarily distinct species and the drivers of its geographic diversity gradient.

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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‘Wallace’s eureka moment: The discovery of natural selection’

 

Dr John van Wyhe, The Natural History Museum


The Natural History Museum 4 July 16:30 – 17:30, Flett Theatre

 


As part of the Wallace100 celebrations taking part in 2013, the Natural History Museum will be hosting a monthly lecture series. These lectures are part of the Museum’s participation in Wallace100, an international programme of projects and events celebrating the centenary of Wallace’s death on 7 November 2013. At these monthly events, leading biologists and historians will discuss different aspects of Wallace’s life and work. The series also highlights the significance of the Museum as a focal point for Wallace collections and studies.

 

The story of Alfred Russel Wallace getting the idea of natural selection in a fit of tropical fever is rightly a famous account of scientific discovery. But what prompted his eureka moment? There have been many theories about Wallace's eureka moment. During his talk, Dr van Wyhe will shed light on these, dispelling many, as he examines the facts and surviving evidence from the time. The truth turns out to be rather different from what we have long believed...

 

Find out the facts at our revealing talk, presented by renowned Wallace expert and historian of science, Dr John van Wyhe. This is the 6th in our series of Wallace100 lectures.

 

John van Wyhe is a historian of science who specialises on Darwin and Wallace. He is the director of Darwin Online and Wallace Online. His latest book is Dispelling the Darkness: Voyage in the Malay Archipelago and the discovery of evolution by Wallace and Darwin (2013).

 

Free tickets need to be booked in advance
Book tickets online
Doors open 16.00

 

Details of the event can also be found here: http://www.nhm.ac.uk/visit-us/whats-on/events/programs/nhm/wallace%27s_eureka_moment_-_wallace100_lecture.html

 

Details of the Wallace100 celebrations can be found here: http://www.nhm.ac.uk/nature-online/science-of-natural-history/wallace/events/index.html

 

Details of Wallace100 events taking place at the NHM can be found here: http://www.nhm.ac.uk/wallace100events

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Tuesday 7th May - 4.00 pm

Mineralogy seminar room

 

Another point of view on sexual selection in prehistoric animals


Dr Rob Knell, Senior Lecturer at Queen Mary University of London. r.knell@qmul.ac.uk

 

Sexual selection is one of the most important driving forces in evolution and is responsible for a tremendous amount of the morphological diversity that we see today. Many of the most charismatic prehistoric animals also appear to carry traits that could be explained as the result of sexual selection: horns, crests, plates, sails and many others. Nonetheless, palaeontologists have traditionally avoided using sexual selection as an explanation for these features and have preferred mechanical, thermoregulatory or species-recognition based interpretations, probably because it is very hard to produce testable hypotheses about the behavioural significance of such traits when we are unable to observe an animal's behaviour. This conservative approach is likely to lead to a significant degree of misinterpretation - sexual selection is a ubiquitous and powerful force and there is no reason to discount it as an explanation for morphological diversity in the fossil record. I will examine the problem of how we can detect sexual selection in the fossil record and discuss issues such as sexual dimorphism, allometry and how it changes with sexual maturity, apparent cost and diversity as potentially helpful indicators of sexually selected features in extinct animals.

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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The great majority of the more than 400 families of snails are found only in the sea, while about 5% of them are exclusively freshwater. Very few snail groups are common in both environments and just three marine families have rare freshwater members.

 

One of these is the Littorinidae (periwinkles), familiar from rocky shores. In the nineteenth century three freshwater periwinkle species (genus Cremnoconchus) were discovered in the mountainous Western Ghats of India, living in fast-flowing streams at altitudes between 300 and 1400 m. These have not been studied for over 100 years.

 

Cremnoconchus.JPGFigure from the original description of Cremnoconchus (images 1-7) Image courtesy of Biodiversity Heritage Library. http://www.biodiversitylibrary.org

 

In a collaboration with scientists from the NHM's partner organisation the Ashoka Trust for Research in Ecology and the Environment (ATREE), Bangalore, David Reid revisited the type localities of the three known species to collect new specimens. (The type locality is the place in which the reference specimen was found that was originally used to describe and name the species.) These were studied to find out more about the snails and allowed the relationships between the species to be investigagted in more detail and revised.  There are distinctive differences between the species particularly in terms of their radula (the rasping tongue of snails), their reproductive systems and the calcified operculum (the disc that fits into the shell opening when the snail retreats into the shell, providing additional protection from predators and desiccation).

 

In addition, an unknown radiation of six new Cremnoconchus species was discovered in the central Western Ghats, 500 km south of the previously known range where David and his collaborators looked at the known species.

 

Cremnoconchus is interesting in evolutionary terms: the current evidence suggests that its closest living relatives are marine snails found only in New Zealand and Australia, suggesting that the ancestral population was split by the breakup of the ancient continent Gondwana during the Cretaceous, between 145 and 65 million years ago.  However, more evidence and DNA studies would be needed to confirm this hypothesis.


Each of the six new species was restricted to a single stream system on the steep western escarpment of the Deccan Plateau, with limited overlap in distribution in two places.  This suggests that populations of ancestral species were isolated by waterfalls or other features allowing evolutionary divergence over time The habitat of these snails is fragile, being very limited in scale and threatened by tourism, road construction and domestic pollution: all the species are judged to be endangered.

 

Reid, D.G., Aravind, N.A. & Madhyastha, N.A. (2013) A unique radiation of marine littorinid snails in the freshwater streams of the Western Ghats of India: the genus Cremnoconchus W.T. Blanford, 1869 (Gastropoda: Littorinidae). Zoological  Journal of the Linnean Society. 167: 93-135.
DOI: 10.1111/j.1096-3642.2012.00875.x

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Life Sciences Seminar

 

Sap-suckers of the Tree of Life: how closely are they related to their feeding branches?

 

 

David Ouvrard

Terrestrial Invertebrates, Dept. of Life Sciences, NHM

 

Wednesday 19 of December 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)

 

 

Sternorrhyncha comprise four super-families among the most damaging agricultural pests. Furthermore, Coccoidea (scale insects - 8000 species), Aphidoidea (aphids, phylloxerans, and adelgids - 5000 species), Psylloidea (jumping plant-lice - 3800 species) and Aleyrodoidea (whiteflies - 1500 species) are driving ecosystems as primary consumers of phloem sap. Various degrees of insect/plant associations, from strict monophagy to high polyphagy, are observed among them and at different classification levels.

 

Until now, several assumptions of co- or ‘parallel-’ evolution between the insects and their host-plants have been made, but rarely using a phylogenetic framework to test these hypotheses. Focusing on Psylloidea, I will trace the macroevolution of these phytophagous insects, from fossil proto-homopterans to the extant fauna, based on the evolution of some striking morphological characters.

 

In parallel, the large-scale analysis of patterns of associations between insects and plants has been made possible using the global datasets compiled and organised in databases such as “Psyl’list” or “White-Files”, originally oriented towards taxonomic information dissemination only. The synthesis of recent taxonomic studies into a revised classification of the Psylloidea offers a framework for further phylogenetic reconstructions, a research basis in the fields of Ecology and Conservation, as well as a management tool for collaborators involved in Integrated Pest Management

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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Ian Kitching, together with colleagues at the University of California, National University of Singapore and the University of Erlangen, Germany, has published a review paper charting the history of Charles Darwin’s prediction of coevolution between a long-spurred orchid, Angraecum sesquipedale, and a long-tongued hawkmoth, Xanthopan morganii praedicta, from Darwin’s first observations in 1862 to the final demonstration of successful pollination in the wild in 2004.

 

Angraecum NaturalHistoryMuseum_PictureLibrary_012880_IA.jpg

Angraecum Sesquipedale

 

Darwin wrote in his 1862 work On the various contrivances by which British and foreign orchids are fertilised by insects, and on the good effects of intercrossing:

 

I fear that the reader will be wearied, but I must say a few words on the Angræcum sesquipedale, of which the large six-rayed flowers, like stars formed of snow-white wax, have excited the admiration of travellers in Madagascar. A whip-like green nectary of astonishing length hangs down beneath the labellum. In several flowers sent me by Mr. Bateman I found the nectaries eleven and a half inches long, with only the lower inch and a half filled with very sweet nectar. What can be the use, it may be asked, of a nectary of such disproportional length? We shall, I think, see that the fertilisation of the plant depends on this length and on nectar being contained only within the lower and attenuated extremity. It is, however, surprising that any insect should be able to reach the nectar: our English sphinxes have probosces as long as their bodies: but in Madagascar there must be moths with probosces capable of extension to a length of between ten and eleven inches!

 

A moth with such a long proboscis, Xanthopan morganii praedicta, was not described until 41 years after the publication of this book, and it was not observed to visit Angraecum until 1992, with further work to prove pollination since then.  Ian and colleagues discuss issues of co-evolution and predation in this excellent paper.

 

Xanthopan morganii praedicta NaturalHistoryMuseum_PictureLibrary_037535_IA.jpg
Xanthopan morganii praedicta


Arditti, J., Elliott, J., Kitching, I.J. & Wasserthal, L.T. 2012. ‘Good Heavens what insect can suck it’ – Charles Darwin, Angraecum sesquipedale and Xanthopan morganii praedicta. Botanical Journal of the Linnean Society 169: 403-432.

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Different ideas of the relationship between the crustacea (crabs, barnacles, copepods and others) and insects have been discussed at length over the past century. The emergence of more and better DNA information is allowing the evolutionary relationships to be explored and clarified.


Ronald Jenner (Zoology) co-authored a first phylogenomic test of the recent hypothesis of a sister group relationship between hexapods (insects) and remipede crustaceans. Numerous data and testing of different interpretations led the authors to robustly find hexapods and remipedes as sister groups.


Remipede crustaceans were first described as Carboniferous fossils in the 1950s (around 310 million years old).  However, living species have been discovered since 1979, living only in underground aquifers connected to the sea. They are slow-moving with relatively basic segmented body plans, but can have specialised characteristics such as poison fangs and advanced sense of scent, important for securing prey in their unusual habitat.

 

NaturalHistoryMuseum_014472_Comp.JPG

A Remipede from Mexico

 

The paper looks at the idea of the Pancrustacea - a large group containing both crustaceans and insects.  The data support the idea that the Pancrustacea can be divided into two major groups.  In the first are the marine decapods (crabs, prawns and lobsters), barnacles and copepods.  In the second group are found the freshwater Branchiopoda (such as the familar waterflea Daphnia), the Remipedes and the insects.  This supports the insects as a part of the Pancrustacea, possibly as part of a subgroup that moved from shallow marine environments to specialist freshwater, groundwater and terrestrial habitats.

.


von Reumont, B. M., Jenner, R. A., Wills, M. A., Dell’Ampio, E., Pass, G., Ebersberger, I., Meyer, B., Koenemann, S., Iliffe, T. M., Stamatakis, A., Niehuis, O., Meusemann, K. and Misof, B. Early online. Pancrustacean phylogeny in the light of new phylogenomic data: support for Remipedia as the sister group of Hexapoda. Molecular Biology and Evolution (doi:10.1093/molbev/msr270)  Abstract

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Bryozoans are widespread aquatic colonial animals living both in the sea (sea mats) and fresh waters, with an extensive marine fossil record over almost 500 million years. Collaborating research groups in the NHM Departments of Zoology and Palaeontology represent arguably the strongest concentration of bryozoan research expertise anywhere in the world.

 

NaturalHistoryMuseum_026159_IA.jpg

 

Wilbertopora woodwardi (Brydone) from the Upper Cretaceous Chalk, Hampshire

 

Andrea Waeschenbach (NERC Postdoctoral Fellow, Zoology), Paul Taylor (Palaeontology) and Tim Littlewood (Zoology) have had accepted for publication the most comprehensive molecular phylogeny of bryozoans to date, using mitochondrial and ribosomal genes.

 

This has resulted in a well supported topology (the shape of the phylogenetic tree), providing unambiguous evidence for the interrelationship of the taxonomic classes.  It also provides strong evidence that several presently recognized taxonomic units at various hierarchical levels are each in fact of more than one origin in evolutionary terms - they are non-monophyletic (a monophyletic group has a single ancestor)

 

Using this topology, the work tried to establish the likely larval form and strategy of the ancestral bryozoans, but this gave ambiguous results.  It seems most likely that multiple shifts have occurred between different types of larval nutrition – dependency on yolk provided to the egg (lecithotrophy) and feeding by the bryozoan larva on phytoplankton (planktotrophy).

 

This result, combined with their long fossil record, promises bryozoans to be a suitable phylum to studying links between reproductive strategy and large scale evolutionary patterns, such as speciation rates. This paper is a significant contribution for assessing the interrelationships in a relatively neglected group that offers much promise as an evolutionary model. This work was funded by NERC (NE/E015298/1).

 

Waeschenbach, A., Taylor, P.D., Littlewood, D.T.J. (2011) A molecular phylogeny of bryozoans, Molecular Phylogenetics and Evolution. http://dx.doi.org/10.1016/j.ympev.2011.11.011

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Robert Prys-Jones (Zoology) is co-author on a new paper on Indian Ocean Parrot biogeography and evolution being published in Molecular Phylogenetics & Evolution. It is the latest in a line of research papers deriving from Robert’s on-going Indian Ocean island research programme, and comprises a comprehensive overview of extant and extinct parrot evolution on western Indian Ocean islands. 

 

NaturalHistoryMuseum_009509_IA.jpg

Psittacula eupatria

 

Parrot diversity around the Indian Ocean is high, with many possible geological, ecological and geographical explanations.This paper examines DNA data from modern and extinct parrots and suggests that the Indian Ocean islands acted as stepping stones in  the radiation of the Old-World parrots, and that past sea-level changes may help to explain distributions and  differences in speciation. A molecular phylogeny shows complex colonisation of Africa, Asia  and the Indian Ocean islands from Australasia via multiple routes, and  of island populations ‘seeding’ continents.


A second paper develops a comprehensive phylogeny of the finches, a large and familiar bird family within which many genus-level relationships have previously been unclear, and is the first product of a co-operation with Dr Per Ericson, Director of Science at the Swedish Museum of Natural History, and is further co-authored by Dr Pamela Rasmussen (Michigan State University Museum), a Scientific Associate of the NHM. The similarity of plumage of finches, and of feeding habits, has in the past given misleading impressions of related groups.  DNA from nuclei and mitochondria give a much clearer and more reliable picture in this paper.

 

  • Kundu, S., Jones, C.G., Prys-Jones, R.P. & Groombridge, J.J. The evolution of the Indian Ocean parrots (Psittaciformes): extinction, adaptive radiation and eustacy. Molecular Phylogenetics & Evolution, Volume 62, Issue 1, January 2012, Pages 296-305. http://dx.doi.org/10.1016/j.ympev.2011.09.025
  • Zuccon, D., Prys-Jones, R.P., Rasmussen, P.C. & Ericson, P.G.P. The phylogenetic relationships and generic limits of finches (Fringillidae). Molecular Phylogenetics & Evolution, in press, http://dx.doi.org/10.1016/j.ympev.2011.10.002
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Greg Edgecombe in the Museum's Palaeontology Department has collaborated with Australian colleagues on the investigation of fossil eyes from the early Cambrian period (515 million years ago).  They published their findings in the prestigious journal Nature at the end of June.


The fossils were found in the Emu Bay shale - a very finely grained rock formed from mud - from Kangaroo Island in South Australia.  Shales can preserve fossil organisms in incredible detail, and those from the Cambrian have yielded an amazing diversity of invertebrate animals that lived in marine environments - those of the Burgess Shale in western Canada are probably the best known.  The Cambrian is of particular interest in evolutionary terms because it was a period at which many new groups of organisms are first seen - the term "Cambrian Explosion" is often used to describe the fantastic and rapid diversification of life in a relatively short geological period.


A fair amount is already known about the eyes of trilobites from this period - their eyes were biomineralized (containing minerals) which meant that the fossils are very well preserved.  However, Greg and his colleagues found fossil eyes that do not seem to have been mineralized - much more delicate structures that have only been preserved because of the exceptional nature of the shale fossils.


The eyes appear to be relatively similar to the compound eyes of modern arthropods - they are around 5-7 mm across and contain around 3,000 individual lenses (ommatidia).  The lenses in the centre of the eye are larger, with a falling gradient in size towards the edge of the eye - creating a bright zone for better sight in lower light.  This structure is characteristic of a modern mobile predator such as a robber fly - more advanced than those of trilobites and not seen in other fossils for a further 85 million years. This emphasises the apparent rapidity and complexity of evolution in this early period.

 

robber crop.jpg

The fossil eyes have similar characteristics to those of modern predatory arthropods such as this robber fly

 

However, a puzzle is that the eyes do not seem to be associated with any identifiable organism in the shale, such as Anomalocaris. It seems possible that the eyes may have been shed in moulting, but by which animal remains to be seen.


 

Lee, M. et al. 2011 Modern optics in exceptionally preserved eyes of Early Cambrian arthropods from Australia. Nature 30 June 2011 474 7353 631-634 http://dx.doi.org/10.1038/nature10097

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