Tag: nature

Help us understand mimicry!

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Picture1I have written about mimicry before, describing why most mimics are imperfect and how some mimics imitate not only the appearance of other animals but also their sounds and behaviour. Now, I need your help with an ambitious experiment to test theories about the evolution of mimicry. Most people know that there are harmless animals that have yellow and black stripes to look like stinging bees and wasps. But did you know that there are many thousands of such species, all with different degrees of “bee-ness” or “waspiness”? The new experiment is designed to compare 56 harmless hoverflies with 42 wasps and bees to measure how similar they are. That’s 2,352 unique comparisons! This information will allow us to test exciting new ideas about the evolution of mimicry. There’s only one catch…

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With his beard and odd dress sense, Uncle Sam would have made a fine entomologist!

This particular experiment will use the human brain as a processing tool and the power of the crowd to generate data. It’s a bit like “Strictly Come Mimicking” (or “Mimicking with the Stars“, if you’re in the US): you just need to rate how similar you think the two insects appear out of 10. I’d appreciate it greatly if you could take some time to run through the experiment below. Don’t do it thinking that there is an end, though – there are 2,352 combinations, remember, and the images are randomly paired on each screen! You can access the experiment here:

www.mimicryexperiment.net

My goal is to reach 10 ratings of each pair of insects. That means a total of 23,520 ratings. I know this is a long shot, but that’s the aim, people! Please do share it far and wide! I’ll share regular updates on the blog as the ratings come in (however many or few there are!).

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“Noble nature”…?

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20161231_184514Walking home after a few drinks on New Year’s Eve, I spotted a small sign in a shop window. The text says:

“As the bee collects nectar and departs without injuring the flower, so should a man behave in his village”

– Dhammapada (1st Century BC)

Two things sprang immediately to mind. The first was the tendency that we have to attribute greater emphasis to quotes from older civilisations, despite the fact that those civilisations are less developed. Older civilisations are not wise like older people – they are actually younger in an absolute sense (as pointed out by Eliezer Yudkowsky). It is as if being from a time far distant to our own confers wisdom that we perceive lacking in contemporary society.

However, the second thing that occurred to be was that “that’s not how bees work”… Pollination is a mutualism most of the time, but not always. By offering a nectar resource in exchange for the transfer of pollen, flowers have evolved relatively straightforward paths to that nectar for their respective pollinators. Sometimes that is a big, open flower that can be accessed by many species, but other times the flower has a peculiar shape or the nectar well is particularly inaccessible. The latter cases often result in very specific species that are able to access the nectar using particular behaviours or very long tongues.Read More »

Clayton Woods and Woodside Quarry

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I’m lucky to live in one of the leafier parts of Leeds, and there is a reasonable amount of green space within an hour’s walk from my home. Yesterday I made my first visit to one such area: Clayton Woods, which turned out to be much more interesting than I was expecting. The woods themselves are pleasant enough to walk through – small dirt tracks weaving through trees and speckled with boulders. There is enough tree cover that the sound from the nearby road is almost blotted out. However, what was most fascinating was what lies at the centre: an abandoned quarry. I had heard about this quarry, but there doesn’t seem to be much information on it aside from a small number of mentions on web forums about the Leeds area. I thought it was worth trying to pull some of that information together here in one place.Read More »

“Camouflage on the edge” – a new paper on concealing colouration

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In 2012, the US Government cancelled a $5 billion camouflage project under which it had already supplied uniforms to soldiers in Afghanistan.  The pattern of camouflage, called the “universal camouflage pattern” (UCP) was supposed to allow soldiers to blend in equally well in forests, deserts, and urban environments but had been deployed but never properly tested to ensure that it provided proper protection.  When this testing was finally carried out, it demonstrated that the camouflage performed poorly, and was actually putting soldiers at unnecessary risk.  It got so bad that US Army soldiers were trading their uniforms with locals so that they could wear something with appropriate colouration.  What this goes to show is how poorly we understand the mechanisms underlying camouflage, even while we spend enormous amounts of money attempting to exploit the phenomenon.  A new paper that my colleagues (based at Carleton University) and I published today in the Royal Society journal Biology Letters adds a key piece to the camouflage puzzle by illustrating for the first time the mechanism behind “disruptive colouration“.  The paper can be viewed for free at the journal homepage, as can all Biology Letters articles, until 30th November 2013 – go browse, it’s a fascinating journal with short, varied, interesting papers.

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A new MOOC from Leeds: “Fairness and Nature: When Worlds Collide”

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Picture1It’s a pretty exciting time to be teaching in higher education.  There has been a wave of critical evaluation (mostly by the teachers themselves) which has led to a great deal of progress over the past couple of years.  This has led to a recognition that lecture-based courses are not the “be all and end all” of university teaching, and that there are better ways to do things.  Massively Open Online Courses (MOOCs for short) are playing quite a large role in redefining how university teachers engage with their students and how we think about delivering the student experience.

The new MOOC from the University of Leeds is called “Fairness and Nature: When Worlds Collide”, and is being run by Professor Jon Lovett in the School of Geography. Jon is a charismatic and passionate guy with a wide range of experiences in the interaction between people and the nature world, and it is these themes that are explored in the course.  If you want to find out more, head over to the FutureLearn site and sign up (it’s free!).  Here’s a taster:

There are some key characteristics of MOOCs that make them different from conventional university courses:

  • Variable length – MOOCs can be anything from 1 week to 12 weeks, with the breadth and depth of content varying accordingly.
  • Entirely online – with no need to rely on built infrastructure, MOOCs can (and, indeed, do!) cater for tens of thousands of students, rather than the usual hundred or so.
  • Flexible study – because of the online nature, students can participate whenever is convenient for them.  Sometimes this means that students drop-off entirely (completion rates are relatively low) but that isn’t really the point of MOOCs.  MOOCs are frequently designed to provide access to education for as many people as want it, and any learning is a bonus.
  • Flexible structure – the online platform allows a wide variety of multimedia, interactive, connected resources to form the backbone of a course.  These make for a very engaging learning experience.

All these factors combine to make a new and interested way of teaching and engaging a wider range of students, and I look forward to seeing where the MOOC movement goes.

Gardens and roofs as nature reserves in cities

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I just heard about this brilliant initiative at Sharrow School in Sheffield (less than a mile from the hospital where I was born!).    One of the school buildings has a roof garden which was specifically designed to represent the various habitats that can be found in the local area.  The garden was so successful that the school was able to have it designated as a local nature reserve under UK law.  You can see more details of the school and the building (including the description of the LNR itself and the justification for the designation).  The roof garden was organised by the Green Roof Centre, an organisation based within the University of Sheffield, when building was created in 2007 during the merger of two local schools to form Sharrow School.Read More »

Dead ducks, homosexual necrophilia, and the importance of anecdotes

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The wonderful world of anecdotes is often scorned by scientists.  Leading journals demand tightly controlled studies with a priori justifications, and this approach has sidelined some of the more interesting and peculiar aspects of academic.  For example, I have a couple of articles that describe trends through space and time in the presence of dragonflies using databases that were collected by enthusiasts in the field.  These kinds of observations are the bedrock of natural history, for example, where initial anecdotes spur pilots studies which result (if the data is supportive) in fully-fledged grants. Another important anecdote was recorded on 5th June 1995, and it has been immortalised with its own (admittedly slightly niche) holiday.  You can see Dr Kees Moeliker talking about his homosexual necrophiliac mallard here:

The first female entomologist: Maria Sibylla Merian

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Maria Sibylla Merian (1647-1717)

I recently visited Amsterdam, where I came across the work of a German naturalist of whom I had not previously been aware.  The Rijksmuseum contains a book that dates back to 1730 and was written by (according to the museum plaque) the “first female entomologist”, Maria Sibylla Merian (1647-1717). The book, entitled De Europische Insecten (available online through the Biodiversity Heritage Library) contains hundreds of illustrations of species made by the author (who also happened to be an extremely talented artist).  You can see some of the detailed illustrations from the book at the Sotheby’s auction page for a copy that is for sale (at £25,000-30,000 it’s a bit out of my price range…) and an example of a page below.

A plate from De Europische Insecten

Merian’s story is an interesting one.  Born into a famous publishing family, her father passed away when she was three years old.  Her mother later married an artist, thus combining the literary and artistic aspects of Merian’s upbringing that would determine her career.  She began at the age of 13 by drawing and painting the silk worms that she caught around her home in Frankfurt.  As a young female artist, she was a popular tutor for the daughters of local wealthy families and this allowed her to both earn a good living and gain access to influential people (and their extensive gardens with all those wonderful insects!).  It was as a result of watching the development of caterpillars into butterflies that she became interested in metamorphosis, and this eventually led to her publication of Metamorphosis insectorum Surinamensium (also available online in its entirety).  This volume, drafted by Merian after a two year visit to the Dutch colony of Surinam in South America (which was cut short after she caught malaria), provided European scientists with some of the first full-colour images of the South American flora and fauna.  Merian undertook that trip at the age of 52 with her daughter, Dorothea Maria, and documented many new species of Lepidoptera, including all stages of the life cycle and the host plant on which the caterpillar lives – a wonderful resource for naturalists back home.  During her visit to Surinam, Merian spoke out against the mistreatment of slaves by Dutch plantation owners and took note of the names that indigenous peoples gave to the species she encountered.

Merian’s work was extremely valuable to Carl Linnaeus, who published in 1735 his Systema Naturae (also available online, but nowhere near as aesthetically appealing at Merian’s work) which laid-out the biological nomenclature that we use today.  In particular, the focus on metamorphosis has led to her being listed among the most influential entomologists of all time.  Merian was honoured with a Google Doodle to commemorate what would have been her 366th birthday on 3rd April 2013.  However, despite all this there is a pretty good chance that Merian died penniless in 1717 a few years after suffering a stroke.  But that is all the more reason to appreciate her work today, which is still among some of the most-highly valued and collectable natural history artwork in the world.

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The copy of De Europische Insecten in the Rijksmuseum, Amsterdam

Species with a chemical defence (but not a chemical offence) live longer

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Dendrobatid frogs are the classic “aposematic” species: they advertise their toxins with bright colours

I wanted to spend a post talking about a new paper that was published recently (3 May 2013) with some colleagues from Carleton University.  It is easy to see the value of tasting bad: predators try to eat you, feel sick, then leave you alone.  Even better if you have bright colours or a strong smell (called “aposematic signals”) to go along with it – that way predators can learn to avoid your colours without having to taste you a second time.  In fact, they don’t have to taste you at all if other animals of your species also have the bad taste and the bright colours.  In theory, this chemical defence should reduce deaths due to predation which means that the prey live longer.Read More »

Green space is good for your health (also, Pope is Catholic)

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This may not come as a surprise to many, but living in an urban environment may not be great for your mental health…  Being constantly surrounded by hustle and bustle, and constantly plugged in to technologies that keep you connected to work and current events, can be a drain. Now a new study, published in the journal Psychological Science in April 2013 (although I can’t find the actual paper online, yet), has provided yet more evidence for an important role of green space in urban areas for the purposes of enhancing “life satisfaction” and general health.  The study used over 10,000 participants, with data recorded over an 18 year period.

It’s worth noting the limitations of this study – it was epidemiological, which means that a lot of variables were recorded and the authors attempted to tease apart correlations between those variables.  The result is that we cannot infer causation.  For example, a clearer result would have been generated by an empirical approach involving a trial with randomly selected people being placed in either high green space or low green space areas, with their mental health measured before and after.  However, it is worth noting that the authors took huge numbers of variables into account when analysing these data, and the datasets are very large.  All of this suggests that the results are reliable.  They also produced a nice, simple video to explain the results in more detail (a great example of outreach by the researchers involved!):

Photo of Roundhay Park, Leeds, by Green Lane (via Wikimedia Commons)