A 3D-printed Homo naledi skull!

H. naledi

Homo naledi has caused a lot of excitement and intrigue in palaeoanthropology and evolutionary biology since its discovery in 2013 by Lee Berger and his team in South Africa. This hominid had many of the characteristics we normally associate with humanoid species that lived around 2 million years ago, having a small brain and curved fingers. But recent analysis has concluded that the fossils could be as young as 200,000 years old – placing it at approximately the same time as early Homo sapiens. So rather than being an ancestor of modern humans, we might surmise that these individuals overlapped with the appearance of our first H. sapiens ancestors. It is not too unreasonable to assume that our appearance might have played a significant part in the extinction of this relic species, given that so many other extinctions coincide with the appearance of modern man.

I have wanted to get my hands on a few casts of humanoid species for years but have always found them too expensive to justify given the small amount of human evolution content typically covered by students in secondary school science curricula and syllabi. Luckily, the discoverers of H. naledi made the fossil scans publicly available, going against the field’s normal habit of protecting the blue prints whilst they carry out tests and so on. I looked up the codes and forwarded them to our tech guy who duly set out to print what resulted in a beautifully detailed H. naledi skull cast. Twenty four hours later I was face to face with Nigel, Nora or whatever the students decide to name him/her.

Surprisingly small yet still recognisibly human-like in form, the cast has made an excellent addition to the biology classroom shelf alongside a model of a double helix and a fox skull found in nearby Baneasa forest. Students love visual aids and will enjoy exploring the skull without having to worry too much about being careful. It took a few hours to print and cost the equivalent of less than five pounds. Obviously the 3D printer was expensive and should be taken into consideration for total cost but now I know a bit more about this amazing technology I will be on the look-out for the codes to print similarly interesting artifacts. Perhaps we will print more bones and get students to assemble the parts. That would be very cool.

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Long-eared Owlet in School!

owlet 1

Owls are nesting opposite the Science Garden! The discovery could not have come at a better time. Poor weather meant I had an hour to alter my lesson plan before Birding Club showed up for their weekly after school activity. An English teacher brought me a photograph of an owlet during a Year 8 lesson. I sent a member of Bird Club in the lesson to investigate. This boy loves wildlife and was delighted to get away from physics questions for ten minutes. He struggles with reading and writing so his recent ecology test score did not reflect the wealth of knowledge he can call upon at the drop of a hat, from naming frog species to describing predator-prey interactions. He has extra time and a scribe for tests but we still have a lot of progress to make before his grades begin to reflect his ability.

We tried to keep the location of the owlet secret to avoid disturbance but by the time Birding Club arrived at the scene, a handful of maintenance staff had gathered. Some were pulling on branches to get a better look and taking flash photographs right up close to the bird. I dispersed them in as polite a manner as possible and a whole school email was sent out in English and Romanian asking for people to keep their distance.

Research from my Birding Club members told us that the owlet is a long-eared,  exhibiting a behaviour known as branching. This is when offspring leave the nest before being able to fly, taking up residence in a nearby branch to spread predation risk. The students were delighted with the bird, showing real concern for its welfare and interest in finding out more about its biology. We located another chick and an adult, perched side-by-side high up in an adjacent pine tree. One of the boys rushed off to grab his sketch book, coming up with a skillful drawing in less than five minutes. I love seeing a different side to students. It’s one of the main joys of running an extra-curricular activity, the less formal structure allowing pupils to express their individual personalities more freely.

We decided to keep knowledge of the location of the other owls within Birding Club to avoid any more disturbances. The boys offered keep watch over the area during break and lunch, thinking up elaborate tales to tell people so they didn’t pass through, including the beautifully simple “Don’t go down there, it smells”. Luckily this morning I found the owlet in a much higher branch in different tree so this wasn’t necessary. Seeing the boys observing the bird completely transfixed, I couldn’t help but feel a little bit envious. I like to believe I feel just as excited by wildlife experiences as I did when I was their age, trying to avoid exaggerating or romanticing childhood events. I was indeed enthralled by the owlet, having never seen a long-eared up close, but looking at the delight on the boys’ faces made me realise I am now harder to please. I either need to build a time machine or see a wild wolf to feel as they did. I am in the right country to see wolves, so I can put the time machine on hold.

On a less positive note, I put a photo of the bird (taken from a sensible distance) on to the school’s daily notices with a plea to keep away from it. Apparently one Year 10 boy asked his form tutor “Why don’t they just kill it?” assuming the owlet must be dangerous. He will be visiting Vacaresti nature reserve with me next month so that will provide a good opportunity to work on his attitude.

owlet 2

A Talk on Rewilding Europe

wisent image

A couple of months ago as part of a Science Week programme, our school welcomed Adrian Hagatis from WWF Romania who came in to talk to a group of thirty students about the work he has been doing in partnership with Rewilding Europe. Adrian drove for three hours to give the talk at no fee, which focused on examples of rewilding in Romania. The talk was well prepared, informative and pitched at an appropriate level. Most of the students in attendance study Biology GCSE or A – level, save for a few keen Key Stage 3 pupils, so it was relevant to the ecology and conservation units that form part of their respective courses. More than this, the talk gave students an impression of the amazing wildlife found within their country of residence and some of the challenges they face. I think too often when reading conservation news and, to a lesser extent, biology syllabi content we are left feeling hopeless at the plight of threatened species.

Adrian’s talk was optimistic, largely focused on the solutions to some of the problems facing species in Romania today, from sturgeon to bison. This left pupils feeling positive but at the same time acutely aware of what they stand to lose as Romanian, European or global citizens without significant action. From reading between the lines of the feedback I received, pupils enjoyed listening to an expert working in the field who could give insights into real examples beyond what a teacher in the classroom could ordinarily tell them!

The school made a donation to WWF Romania to show our appreciation and I have spoken to members of their education department about building a long-term relationship that will involve Sixth Form students going to visit European bison release sites. Two of my Year 12 biologists were particularly inspired by the talk, staying behind to ask Adrian questions about back-breeding eurochs and his opinions on mammoth cloning. He dealt with the questions in a sensitive matter-of-fact way that satisfied the pupils’ curiosity until we had to call it time for next period. I must make sure a trip is planned to take place before this time next year when these pupils will be sitting their final A2 exams.

Given that a lot of our pupils are from powerful, influential Romanian families I hope a few of them took home the message and raised awareness in parents. Perhaps it will shape some of the students’ own decision making after they land or inherit powerful positions themselves. Here’s hoping.

Book Review – The Cuckoo: Cheating by Nature by Nick Davies

the cuckoo

I was inspired to pick up this book after seeing a rufous female common cuckoo on my recent trip to the Danube Delta and listening to an enjoyable interview with Nick Davies on The Life Scientific podcast during a hair-raising drive home through an unseasonal blizzard.

Davies is Professor of Behavioural Ecology at the University of Cambridge and has studied cuckoos on Wicken Fen since 1985 (the year of my birth, pleasingly). The Cuckoo is a mixture really of Davies’ memoirs as a field ecologist and the science behind brood parasitism. He describes how his experiments have led to interesting findings about cuckoo evolution and the arms race they are engaged in with their hosts. He describes the functions behind aspects of cuckoo morphology and why some specialist sub-species are better at mimicking host eggs than others, this largely being due to the amount of time that the host species has been under significant selective pressure to reject odd-looking eggs. He draws upon lots of fascinating examples of other parasitic bird species and non-parasitic cuckoos from around the world from Japan to West Africa. Davies makes the very valid point that perhaps we should regard UK cuckoos as being an African species given that they spend twice as long living next to lowland gorillas than alongside cattle in Britain! One of the most interesting parts of the book for me was the explanation as to why cuckoos roughly resemble sparrow hawks, particularly the presence of barring, having not previously noticed the similarity myself.

Davies’ accessible, clear style of writing reminded me of first reading The Selfish Gene in my second year of university. I remember feeling as though what seemed like lots of stiff, fusty facts suddenly fit neatly together into a beautiful and exciting overarching concept. Before reading The Cuckoo I thought – “Cuckoos. They’re brood parasites that overwinter in Africa”. Reading The Cuckoo, I have learnt that there is a lot more to them!

Davies cites the work of Richard Dawkins and John Krebs a few times in the book which gives a good refresher on the ideas of kin selection. In chapter nine Davies claims to have disproved Dawkins and Krebs’ suggestion that cuckoo chicks rely on manipulation (as opposed to deception at the adult stage) to trick the host species into feeding it. Dawkins and Krebs likened the urges of a reed warbler, for example, to feed any begging mouth within its nest to the compulsion of a drug addict to get their next fix. Davies tells us that his findings show reed warblers will readily accept the chicks of other species besides the cuckoo, such as dunnock, and thus the drug analogy is wrong. Now, perhaps an analogy is not the most robust of ways to present a scientific idea but I think Dawkins and Krebs’ holds firm. The cuckoo chick is manipulating the reed warblers’ instinct, insofar as it is taking advantage of the host’s inability to resit feeding a gaping mouth within its nest, even if dunnocks are not doing so as a life-history trait. I can’t help but think deception would be the wrong word to describe the cuckoo chick’s behaviour because the reed warbler does not necessarily believe the cuckoo is its own genetic offspring but it might simply be so full of hormones that it can’t resist the urge to provide it with food. Davies describes how even now when observing in the field he is perplexed by the sight of a reed warber feeding a cuckoo chick eight times its own size. Maybe I have misunderstood Davies’ argument. Perhaps Dawkins and Krebs’ are correct in their thinking but should move away from the ‘junkie’ analogy to explain it. See what you think.

The book ends with a reflection on how and why the UK cuckoo population has reduced so drastically over the thirty summers during Davies’ observations – a sombre but unsurprising end. I have heard older family members talking fondly about how the call of a cuckoo was a common sign of spring when they were growing up. It makes sense alongside the figures that I was 31 years old and in Romania by the time I had my first good look at one.

If you are looking for a popular science book that is sufficiently evidence and data loaded to back up statements without requiring regular re-reading of paragraphs (Yes, I am thinking of A Brief History of Time) this is an ideal choice. I read one chapter per night and always looked forward to the next. I’ll be adding The Cuckoo to our school’s library collection in the hope that raising awareness in young readers (15+) makes some small contribution towards reversing that downward trend in cuckoo numbers. 4/5