Perspectives Archives - Page 17 of 24

15/11/201306/11/2013

How Good is the Fossil Record?

One of the projects I’ve been working on recently has concerned diversity in the fossil record. In broad terms I’m looking at how diversity has changed over the last 540 million years, a period known as the Phanerozoic which starts at the Cambrian explosion and continues to this day. I want to try and understand what causes the periodic increases and decreases in diversity.

I’m not a palaeontologist, so this work has involved a massive learning curve in order to understand how we know what we know about the fossil record. What I’ve learned has led me to have an enormous respect for palaeontologists, but to also wonder whether some of the claims made on the basis of evidence from the fossil record may not be slightly overstated.

If we compared the fossil record to a court trial, I’d argue that the public perception is that the fossil record is rather like the court transcript: a full and complete record of the history of life on earth. Scientists outside the field of palaeontology probably understand that this is not true, and may liken it to more of a newspaper report on the trial: summarising, missing some details but the key facts are in place. The more I look into the fossil record, the more I think it seems like the hear-say testimony of an unreliable witness: heavily biased, missing important facts and giving probably erroneous information.

Before I get angry palaeontologists shouting at me I want to emphasise that that for short timescales or small areas I think the fossil record is brilliant and we can learn a lot about species turnover and ecosystem development. My concern comes from combining these short timescales and small areas and then using them to produce long timescale, global patterns of diversity. While it may seem like this is a sensible way to produce this data – who could possibly sample the entire earth for the entirety of the fossil record by themselves? – there are a number of so-called sampling biases that I feel make this approach potentially troubling. And while I have seen a great deal written about these biases and the efforts to reduce their effects, I have also seen research that makes me think these biases are impacting the data in ways we cannot predict.

So, after all that build-up, what are these biases? You’ll forgive me if I don’t discuss them all here, there are so many. Instead I’m going to split them into two groups and discuss these groups in very broad terms, focusing on the ones I think have the potentially biggest impacts on the patterns of diversity at the global scale. Proper palaeontologists have used a variety of different groupings, but I’ve grouped them into taphonomic biases and taxonomic biases. Taphonomy is the process of fossilisation but in this discussion it will also involve the process of the discovery of fossils. Taxonomy is the naming of species and there are a surprising number of biases that result from this seemingly simple process.

The most obvious taphonomic bias is that of the potential for fossilisation. It has been estimated that less than 10% of living species would end up in the fossil record and it would be heavily biased towards those organisms with bones or shells [1],. Many of the fossil diversity analyses are performed on molluscs as they have a good fossil record, so you might think that this would remove this problem. But the type of fossilisation affects how well an organism is preserved, if at all, and this affects molluscs just as much as other animals [2]. Plus, using molluscs assumes that they are a good model and representative of all organisms over all time which seems to be asserted without much evidence.

Another taphonomic bias is that of true sampling. At one end, not all environments are fossilised and at the other, not all fossil beds are studied by palaeontologists. In between, some fossil beds may be eroded over time and others may never reach the surface to be exposed for study. This leads to an effect called the ‘Pull of the Recent’ [3] whereby diversity increases towards the present day simply because there are more rocks available to study; the oldest ones have eroded, and the ones left are fewer in number the further from the present you go.

This sampling is not only biased in time, it is biased in space. There is a global trend in biodiversity, with highest levels at the equator and lowest at the poles, called the Latitudinal Diversity Gradient (LDG) [4]. This trend occurred throughout much, if not all, of the Phanerozoic and means comparisons of fossils between time periods must be from similar latitudes otherwise changes will say nothing about global diversity. While we may talk in terms of ‘global diversity’ it is often based on limited samples that may be predominantly from the tropics in one time period and temperate latitudes in another, yet this is rarely considered as a compounding factor when diversity is discussed.

Taxonomic biases are no less concerning. Naming fossils is more complex than naming living organisms, as the names must be based purely on the (potentially incomplete) skeleton. It is increasingly common to find living organisms that look identical but are genetically distinct species, and conversely organisms that look very different but are simply displaying phenotypic plasticity [5] yet fossils are named on the basis of their (potentially misleading) morphology which can significantly affect diversity estimates. Then there are problems of widespread fossils being given different names in different countries, or long-lived fossils being given different names in different geologic periods. Finally, there is the fundamental problem that the fossil record shows species evolving, and someone has to decide if and when a new species has formed and a new name applied. This will present itself in the data as an extinction and origination event, even when the population may not have changed in size or location.

These are just the very tip of an iceberg of biases. It may well be that palaeontologists have answers to all these biases and I have just failed to find the relevant literature. So far all I have found seems to be the claim (hope?) that all the biases will cancel each other out, leaving the true biological signal visible. I can’t be so certain. Indeed, my greatest fear is that the patterns of diversity are nothing more than the product of these biases and have little relation to the actual changes of diversity over the history of life on Earth. Reassurances to the contrary would be most welcome!

1. Nicol, D. (1977) The number of living animal species likely to be fossilised. Florida Scientist. 40, 135–139

2. Martill, D. M. (1998) Resolution of the fossil record: The fidelity of preservation. In The Adequacy of the Fossil Record (Donovan, S. K. and Paul, C. R. C., eds), pp. 55–74, John Wiley & Sons

3. Raup, D. M. (1972) Taxonomic diversity during the Phanerozoic. Science. 177, 1065–1071

4. Hillebrand, H. (2004) On the generality of the latitudinal diversity gradient. The American Naturalist. 163, 192–211

5. Bennett, K. D. (2013) Is the number of species on earth increasing or decreasing? Time, chaos and the origin of species. Palaeontology. in press,

Author and Picture Credit:

Sarah Hearne: hearnes[at]tcd.ie, @SarahVHearne

11/11/201306/11/2013

Conference season madness!

Over the last month or so you’ll probably have noticed that a lot of posts on EcoEvo@TCD are essentially “what I did on my summer holidays” essays. Luckily, I think most of us did quite a lot of interesting and scientifically relevant things! My summer this year seemed to be full of conferences, so I thought I’d write a quick post describing them, and what I liked or disliked. This post was inspired by Britt Koskella’s excellent post on the same subject; although Britt attended NINE conferences this summer so is clearly completely insane.

Over the summer I attended four international conferences: Evolution 2013 in Utah, BES Macroecology in Sheffield, International Mammalogical Congress in Belfast, and ESEB 2013 in Lisbon. This involved 15 days of conference going, four plenaries, one prize talk, eight invited talks, 103 standard talks, and 56 lightning talks. So in total I spent about 40 hours in talks, not including questions or people running over time…

Evolution 2013, attended by around 1500 people, was in late June, and was probably my favourite conference academically. I’ve been going to Evolution since 2006 and have only missed three meetings in that time, so it’s the conference I know the most people at, and is most closely aligned with my interests in macroevolution. Most of the top names in the field were there, and I saw some excellent talks. I particularly enjoyed the plenaries. Richard Lenski’s plenary reviewed 25 years of experimental evolution using E.coli in his lab, Dolph Schluter’s discussed ecological opportunity as a factor in increasing rates of diversification, and Jack Sullivan talked about advances in systematics since the last meeting at Snowbird (although this talk was mainly notable for the “dirty chipmunk sex” and pictures of ground squirrel bacula – look them up on Google!). The plenaries at Evolution are generally entertaining and thought provoking, and in recent years there seems to be a trend to talk about something controversial. This is great and I think that’s how plenaries should be! The other big highlight was the location. It was up in the ski resort of Snowbird at 8,000 feet, so we were surrounded by snowy mountains, cheeky ground squirrels, marmots and even the occasional moose. On the flip side, this year’s Evolution was smaller than usual (or felt smaller) because fewer European scientists made the trip. With ESEB (the European equivalent of Evolution) and INTECOL happening in August many people decided to attend these instead. This made it feel a bit more US-centric than usual.

My second conference of the summer happened two days after I got back from Utah and was in the less exciting location of Sheffield (sorry Sheffield, you just don’t have enough moose). This was a much smaller conference with only 60 attendees. The great thing about this was that I was able to briefly chat to almost everyone at the conference. In addition, many of the attendees are old friends of mine so it was lovely to catch up with them. This was a British Ecological Society special interest group meeting on Macroecology (if you’re UK or Ireland based I’d definitely recommend checking out any of the BES special interest groups, they’re friendly and full of enthusiastic people!). We spent the two day meeting listening to five minute talks from anyone who wanted to present, then had panel discussions after the talks which worked really well. We also had some “break out” groups to discuss the future of the field. The most interesting of these for me was – “If we got £20 million from the government today what would we spend it on?” Amusingly this mostly boiled down to people wanting more, and better quality, data! The highlight of this meeting for most people was Ethan White’s excellent plenary. I’m sure it would have been mine too but I had issues with my train and ended up being two hours late and missing his talk (sorry Ethan!). The train also “ate my homework” (I had to stand all the way on the later train so didn’t get chance to write my talk). I promise to do better next year!

My third conference was the 11^th International Mammalogical Congress in Belfast. Full disclosure – I’m not really a mammalogist (I work on mammals, but just because the data is good) so this was an odd one for me. But Belfast is only two hours away on the train and my PhD students thought it would be fun to present their posters more than once. Organisationally this was a strange conference (no offence intended). The talk program wasn’t online so there was a lot of frantic flipping through the booklet to try and find talks. There had also been a change to the program that removed the second poster session, meaning that one of my students turned up a day late to present his poster. However, I saw some really interesting talks, particularly in the disease ecology symposium. I also saw the worst set of PowerPoint slides I’ve seen in a long time – lemon yellow background, brown text with shadows, no pictures and text completely covering each slide! Yeurgh!

My final conference of the summer was ESEB 2013. This was a lot of fun and I saw some excellent talks. I also discovered that I don’t understand population genetics. At all. I think by this point I was “conferenced-out” so it was a difficult conference for me. Also because of the overlap between INTECOL and ESEB, a lot of people I would normally catch up with there were at INTECOL instead. This was particularly reflected by the paucity of macroevolution talks and attendees with macroevolutionary interests. In fact, our delegation (myself and five students) from TCD was probably the biggest group of macro-people there! This meant there were a few days where I found it hard to find many relevant talks. I still attended some very interesting talks, but I also spent a lot of time feeling very stupid because I attended lots of talks I didn’t understand at all! The highlight of this conference for me (partly due to my macroevolutionary interests, partly due to my love of pretty slides) was Rich FitzJohn’s JMS prize talk. The content was good but the slides (all made in R apparently!) were gorgeous. I also really enjoyed Hannah Kokko’s talk where she was able to describe quite complex maths in a really accessible way. The other, less academic, highlight was tweeting a picture of some Superbock – a local beer – and the beer company replying, thus ruining the conference twitter feed by filling it with pictures of beer! Oops!

My conclusions:

1)Four conferences in a summer was too many conferences! Each was fun in it’s own way, but conferences are exhausting both mentally and physically (often talks start early and social events end late) so I ended up feeling totally wiped out for weeks afterwards. Next year I think I’ll focus on two or three at most.

2)Feeling stupid at a conference is inevitable at some point, but it doesn’t mean that you are stupid. When I was a PhD student I felt stupid all the time, but as I’ve become more seasoned I’ve realized that often it’s because the speaker isn’t explaining themselves properly, or because it’s so far out of my field that I don’t know the background. If you don’t understand, try and discuss it with others afterwards. We’ve been doing this a lot after seminars recently and it’s really helped my understanding of the trickier bits.

3)Big conferences are great for meeting lots of people you know already, but terrible for making new connections. From now on I’ll try and go to one big conference a year to catch up with old friends, and one small conference where I can meet new people.

4)Going to four conferences made me realize how cliquey a lot of evolutionary biology is. Many of the people speaking in symposia had also spoken at symposia in previous years. In some cases people spoke in symposia at multiple conferences (and gave almost the same talks). This is inevitable to some extent and shows the importance of having a good network within your subject. Next year however, instead of moaning I’m going to organize my own symposium and try to invite some people I don’t know, plus women and early career researchers. I’m also going to make more of an effort to attend small conferences where I don’t know lots of people.

5)Twitter is an awesome way to improve your conference experience (see my other blog posts on this). But don’t tweet too many pictures of Superbock…

Author: Natalie Cooper, ncooper[at]tcd.ie, @nhcooper123

08/11/201307/11/2013

Trophy Hunters

Antler collection at Harvard's Museum of Comparative Zoology — Antler collection at Harvard’s Museum of Comparative Zoology

It may be an inconvenient truth in these conservation-focused times but we owe a debt of gratitude to the trophy hunters; the army officers and colonial-types who killed animals for sport and prestige. Without their considerable efforts, the vaults of natural history museums would be devoid of the skeletons and skins which form the bases of both exhibitions and many PhD and MSc. theses. Of course, were it not for the over-zealous efforts of hunters perhaps many charismatic animal species wouldn’t be so endangered now but let’s focus on the positives here…

Naturally, if you’re a hunter looking for a prize, bigger is usually better. It’s far more impressive to have a stag or bear’s head mounted on your wall than a hedgehog or shrew – although I would like to hear the embellished stories which might arise from tales of killing your first hedgehog! Similarly, if you are a taxidermist or museum collections manager in many ways it is easier to prepare and preserve large rather than small mammal specimens.

These collection trends are all well and good if you’re interested in the charismatic species. I, however, am studying the little shrewy-type things; hedgehogs, moles, shrews, golden moles and tenrecs – fascinating species but not prized possessions for your trophy case. Even in some of the world’s largest natural history museums it’s difficult to find intact skulls and skeletons of some of these creatures. Combined with the inherent delicate nature of these animals (some tenrecs’ limbs are tiny!) compiling a complete morphometric data set of the groups remains challenging.

Tenrec limbs with a pen for scale; teeny tiny tenrecs!

For the museum collections of these little critters that do exist; I am eternally grateful to the progenitors of carefully handwritten labels accompanying the skulls and skeletons on which my PhD research depends. Adventurers such as Major Forsyth, G.K., Creighton, and C.J., Raxworthy who donated specimens from their tropical voyages deserve special thanks in any research which arises from their collective efforts. However, I am also grateful to the back-yard naturalists, the people who collected and preserved the seemingly ordinary, every-day species of common shrews and hedgehogs which are no less important to ecological and evolutionary research than their exotic counterparts. I benefitted greatly from their collective efforts during my recent trip to Chicago’s Field Museum.

Whether naturalists or trophy hunters, the individuals immortalised by museum specimen labels couldn’t possibly have envisaged all of the diverse future research which would be based on their prized collections. It’s an important reminder that, despite the inherent appeal of flagship species, the lesser-spotted or common-something-or-others are just as deserving of our attention and study. Even if you don’t have the equipment or inclination to start posting skeletal remains of common species to your local natural history museum, there are still plenty of ways of contributing to the study of “ordinary” wildlife. Don’t be dazzled by the allure of large-animal trophy hunting and remember that, when it comes to understanding the natural world, bigger is not always better.

Author:

Sive Finlay: sfinlay[at]tcd.ie

@SiveFinlay

Photo Credits

Sive Finlay

29/10/201321/10/2013

To tweet or not to tweet, that is the question…

This August I celebrated one year of being on Twitter. On the auspicious occasion of my Twitter-versary I decided it might be useful to reflect on the year. Did I get what I wanted to get out of the experience? Did I get other things I didn’t expect? Or did I just find myself an amazing way to waste a lot of time? Should I continue my affair with the Twitter-verse? (SPOILER ALERT – I’m obsessed with Twitter so of course the answer is an emphatic yes!)

What did I want to get out of the Twitter experience?

For some reason TCD doesn’t have much of an international reputation in Ecology and Evolution, despite a strong record in publishing papers in the area. In fact, when I started working here in January 2012 a lot of people were surprised that TCD had science departments! Clearly this needed to be fixed if we were going to attract high quality students and postdocs to our groups. A couple of my friends had been raving about Twitter for a while so I decided to give it a go. I also convinced Andrew Jackson to start actively using his account and over the course of the year we’ve got most of the ecology and evolution postgrads and staff on Twitter as well. The overall aim was a mixture of selfish self-promotion, and slightly more altruistic promotion of the School of Natural Sciences and our research.

Did I get what I wanted from Twitter?

I’ve been thinking about this a lot and surprisingly I don’t think I did (carry on reading below for some unexpected benefits which totally outweigh this “failure”). This is mainly because I had really unrealistic expectations of what Twitter was going to do. I had visions of hordes of potential students and postdocs contacting me. However, the reality is that, at present, I have not had anyone contact me via Twitter looking for PhD or postdoc funding opportunities. When we advertised a Chair in our department I don’t think anyone who applied saw the advert on Twitter. However, I do think some of these things will happen in time. It’s important to remember that building a Twitter following requires effort and takes a long time. It’s also really hit and miss – sometimes a tweet will get loads of retweets and replies but a similar tweet will be left to float into a black hole of nothingness. And sometimes no-one comments but everyone reads your tweet and remembers it. So it’s pretty impossible to gauge your impact.

In the interests of honesty, there are also a few other downsides to Twitter that I’ve outlined below.

Downsides I: The echo-chamber effect

This has been mentioned by lots of people, but essentially you follow people with similar opinions to yours, and vice versa. So you only see tweets from people with these similar opinions leading you to believe everyone agrees with you. I have a simple way to remind myself that this isn’t the case. Every now and then I’ll look at what’s trending in Dublin/Ireland/globally. Five minutes reading tweets about Harry Stiles from One Direction (“He’s a cupcake not a man-whore!”) are more than enough to remind me that not everyone in the world thinks about things like I do.

Downsides II: Negative tendencies

I’m not sure if this is a trait common to all scientists, or if it’s that Twitter breeds gloom, but there is a lot of negativity about academia on Twitter. Mostly this revolves around the difficulties of getting a permanent academic position, the problems of being a woman or a minority, issues with scarcity of funding, or general gripes about writing up your PhD thesis. All of these problems are real and frustrating, and it’s great to vent about them from time to time. However, if you’re already miserable then reading a whole load of negative comments can sometimes make you feel even worse. I think this is generally balanced by the other more positive aspects of Twitter but I do sometimes unfollow the most gloomy people! This leads me on to the unexpected benefits of Twitter.

Unexpected benefits I – Support

As I mentioned above, people often use Twitter to vent about the bad aspects of academia. The great thing is that when you do this there’s always a couple of people there to make you feel better, and like you’re not alone. Generally these people don’t know you personally, so it’s just a nice altruistic outpouring of support. On the flip side, when things go well people are also ready to congratulate you and encourage you. This is a wonderful and totally unexpected benefit of using Twitter! I’ve also had the great pleasure of meeting many of my Twitter friends in person recently. These are often people completely outside my area of research but they totally delightful human beings to hang out with (even if it’s extremely odd to talk to them rather than keeping it to 140 character messages).

Unexpected benefits II – Radically improved conference experiences

I enjoy conferences, but using Twitter has catapulted them into a whole new level of usefulness and enjoyment. Even just passively reading Twitter feeds during conferences I’m not attending is fascinating, and a great way to keep up with fields I’m interested in when I can’t attend the conference. When I’m at a conference, I find live tweeting really helpful for keeping myself alert and engaged in the talks, it’s an excellent way to keep notes and it allows you to interact with people who aren’t at the conference or to discuss talks with people at the conference even as the talk is being given. I also really enjoy meeting other Twitter-ers (is that a word?!) in person. This is particularly useful at conferences where I don’t know many people.

Unexpected benefits III – Resources

I already wrote a blog about the ways you can use Twitter to save time so I won’t repeat it here, but basically I’ve found links on Twitter to everything from newly published and relevant papers, statistical tests I need for my research, information on hot topics in academia, conferences, funding opportunities, resources for students etc. My students have also used it to get advice on their PhDs and side projects.

Unexpected benefits IV – Funny animals to ease the troubled mind.

Finally, if you’re ever down, avoid the gloom-mongers and look for people posting GIFs, videos or pictures of funny animals. There are few levels of gloom that cannot be alleviated by a video of animals using trampolines or my personal favourite, animals fitting into tiny spaces.

So in conclusion I think the benefits FAR outweigh the negatives of Twitter. If you haven’t tried it yet, have a go! If you have and I follow you, thank you, you’ve made my life a more interesting, engaging and hilarious animal-filled place.

Author

Natalie Cooper:ncooper[at]tcd.ie

@nhcooper123

Image source

www.binoyxj.com

11/10/201305/04/2019

Big is better!

Reflections on geeking it up at Intecol 2013 by Jane Stout

Having not been to a 2000+ delegate, multi-session, international conference for several years, I was a bit nervous in the run up to INTECOL2013 “Into the next 100 years: advancing ecology and making it count” – would it be possible to see all the talks, read all the posters and meet all the people I planned to? (Answer: no). Would I remember everyone and would anyone remember me from past meetings? (Answer: some yes, some no – thank goodness for name tags). Could I follow in the footsteps of Katie Taylor, the last girl from Bray to take the stage at the London ExCeL Arena, and take the Olympic gold? (Answer: no; note to self: must try harder). But I needn’t have worried – INTECOL 2013 was excellent: it was well organised, the quality of the science was top-notch, the sun shone, and the whole thing was very inspiring and humbling. Continue reading “Big is better!”

07/10/201324/09/2013

When Perseverance Pays Off

The history of science is, as the name suggests, the study of the historical side of science: the people, the process and the development of the knowledge and techniques that have made science the dominating force it is today. In popular culture the history of science is often told through individuals: the mavericks and geniuses so singular that only they could see the right path to take. The problem with this approach is that it does a mis-service to the hundreds and thousands of people who have worked so tirelessly to make the incremental advances in knowledge that accumulate until the snowball has built into an avalanche and the paradigm is ready to be shifted by whoever is lucky enough to see the pivot first (to hideously mix my metaphors).

Yet there are times when the ‘maverick’ status is not unwarranted. Often the term is used pejoratively to describe someone who will not let go of an idea long-since disproved. But on occasion there are people for whom the inability to give up pays off; and it’s one such person I wish to discuss here today.

The set-up: Otago, South Island, New Zealand, early 1910s. A boy stands in the local museum looking at an old black and white photo of a bird. This bird is unlike any he’s seen. It looks like a pukeko (a large moorhen-like bird) but it is maybe twice the size and three-times the bulk. It has a sharp yet heavy bill that takes up the entire front of the face; a stocky neck and strong bare legs. The legs and bill are the same colour but differ from the dark body. The feathers show signs of different colours on the back and wings though the black and white makes it difficult to be certain. The boy stares, enraptured, and looks at the label: Notornis (Maori: Takahe; Porphyrio hochstetteri): Extinct.

The boy was Geoffrey Orbell, and despite being told (probably repeatedly) that the takahē was extinct and had been since the 1890s, he continued to believe that they were still out there, hiding. Fiordland, the area where takahē were last seen alive, was still relatively unexplored and the mountains and valleys could easily hide a small population, or so Doc (as he was nicknamed due to his medical degree) believed. With a small group of friends he spent his free time tramping through the Murchison Mountains in search of the elusive (and supposedly extinct) bird.

I don’t know how long he searched, how many miles he tramped, how many friends he bored and how many false hopes he had dashed. But I do know that in 1948 he did what no one thought possible: he found a population of living takahē (the name now commonly used).

The discovery caused an immediate reaction and for a while Dr Orbell and his friends were international stars. Scientists hiked to the valley where the takahē had been found and, unusually for the time, recognised the importance of the discovery. Efforts to protect the birds were rapidly put in place. In a news report from 1950 (well worth watching for voice-over and musical accompaniment if nothing else) the population was estimated at 10 breeding pairs, yet this may have been an underestimate as the population was said to reach a low in 1982 of 118 birds.

Until the 1980s the takahē were largely left in peace but a steep decline in population numbers forced the New Zealand Department of Conservation (DOC) to step in. A captive breeding programme combined with translocation to predator-free reserves increased the population to 263 at the beginning of this year. This may not seem impressive for 30 years of active conservation but takahē, in common with many of New Zealand’s endangered birds, are classic K-selected species meaning they live a long time, are slow to reach maturity and have few offspring over the course of their lives.

Predatory rodents that prey on eggs and chicks and inbreeding depression are the main factors that hinder more rapid population growth. Luckily New Zealand has recovery strategies for many of their endangered species which involve the use of predator-free islands and mainland reserves. While little can be done to improve the genetic diversity, strenuous efforts are made to maintain it through closely monitored breeding programmes.

Takahē may not be completely safe from extinction, without active conservation they would almost certainly be extinct. If it were not for Dr Orbell and his passion and determination in the face of almost certain defeat it is highly likely that the takahē would have died out, high up in the mountains and with no one to mourn their loss.

Dr Geoffrey Orbell was an ear, nose, throat and eye doctor whose search for the takahē was just one part of his long and fascinating life. He died in 2007 at the age of 98 and was born on October 7^th 1908. Happy Birthday Geoffrey!

Author:

Sarah Hearne; hearnes[at]tcd.ie, @SarahVHearne

Photo Source:

Wikicommons

27/09/201317/09/2013

Dear students (part 2)

Part 2 of our lecturers’ letter of advice to their students …

Dear students,

We really enjoy teaching you but there are some things we wish you knew…

6. We don’t want you to fail your exams

Every year people come out of the exams complaining (or sometimes weeping!) about how they’ve definitely failed and the lecturer was clearly being mean on purpose so everyone would fail. This upsets us because it shows that you don’t trust us to be decent human beings and/or professional educators. Generally speaking, everyone does fine on the exams we set. If, for some reason (and its rare) everyone does obviously badly on an exam then it may be the case that something was misunderstood or an inappropriate question was set. When this happens we usually re-mark the exam or change the marking scheme appropriately to make it fair, and so that the number of people who pass is in line with the other exams.

7. Getting 59% overall for the year doesn’t mean you were 1 mark away from a 2.i

Your final year mark is made up of all the coursework you’ve done, plus your exams, and comes out of a total of about 1000 marks. So 1% is not equal to 1 mark. For example, if 50% of your course was continuous assessment and you got 60%, you still need 60% in your exams to get 60% overall. Often a single percent overall means finding 10% more from an exam, the equivalent of changing your grade for an essay from a 2.i to a 1^st. Sometimes it is possible to find an extra mark or two but 10% suggests that the person marking the exam made a serious error, which is very unlikely. At Trinity College Dublin everything in the final year is marked, then checked by at least two other people, one of which is an external examiner who keeps standards level with those across Europe. The project is independently marked by at least two people, as well as being checked by the examiner.

8. Collective success might be more akin to collective mediocrity

Studying as part of a group can be a fun way to revise for exams, and provide a challenging environment where you can bounce ideas off each other and learn. However, there is a potential downside. Exam study groups can often produce generic essays that have been carefully prepared by the collective. In the worst case scenario, this can drag everyone towards the mean. Furthermore, unoriginal and repetitive answers can bore the pants out of the person marking them.

9. Question spotting is a terrible idea

People have somehow got the idea that they can get away with only studying one or two topics before an exam because the same topics come up year after year. Whilst this is true, precisely the same questions do NOT appear each year, and at some point we may stop using any given topic. This question-spotting leads to people learning the “answer” to a previous year’s question and trying to apply it to the paper in front of them. Not answering the question before you in the exam, but instead regurgitating and shoe-horning in a prepared answer will not gain you marks. By all means be strategic in your revision but make sure you cover the whole course, but even more importantly, make sure you answer the questions you are given. Never rely on topics remaining the same from year to year – course content changes, as do lecturers, so you may find yourself in a situation where none of your topics come up if you only revise some of them. If that happens it’s no-one’s fault but your own!

10. Education is a privilege. Enjoy it!

Believe it or not, we hate exams as much as you do! However, we need to assess students somehow; we can’t just give everyone a degree. If we did, what would be the point in studying? Because of this, exams remain part of being a student. Notice that we say “a part” of being a student. As a student you should be here to learn as much as you possibly can from some of the leading academics in your subject. You should not be trying to learn as little as possible so you can pass an exam. Yet the question we get asked the most is “what do I need to know for the exam?”. This is infuriating because it implies that only knowledge needed to pass the exam is valuable, when learning for the sake of learning is one of the most wonderful experiences in life. In addition, many of the things you’ll learn as a student, like presentation skills, teamwork, communication skills, time management etc. are not worth any marks in exams. But these are the skills employers are looking for. Don’t waste the opportunity to improve your career prospects and general knowledge of science just because it doesn’t count towards your final grade. Education is about so much more than that.

Yours sincerely,

Natalie Cooper & Andrew Jackson (Assistant Professors at TCD)

@nhcooper123 @yodacomplex

ncooper[at]tcd.ie, a.jackson[at]tcd.ie

Image source:

readingforall101.blogspot.ie

23/09/201317/09/2013

Dear students (part 1)

In the first of a two part post, Zoology lecturers address their students…

This week marks the beginning of another academic year at Trinity College Dublin. We’re sure staff and students alike are greeting this news with a mingled sense of excitement, anticipation and dread (!).

Near the end of last term, some of us were discussing things we wish undergraduate students understood about lecturers and the academic process, so we thought it might be fun to post this here. If any students would like to reply to this please do, we welcome your input! But please keep it polite and respectful. Most of this is aimed at the Sophister years (3^rd and 4^th year students) but most is applicable whatever stage you’re at and wherever you are studying your degree.

Dear students,

We really enjoy teaching you but there are some things we wish you knew…

1.We have feelings too!

To steal from Shakespeare: “If you prick us, do we not bleed? If you tickle us, do we not laugh?” We’re not suggesting that you attack us with pointy objects or start tickling us, but the point is that lecturers are human beings, not robots [Though I’d love it if I had a robot to do my lectures sometimes, it’d be awesome if it would also clean my house and the Zoology microwave!]. It sometimes feels like undergraduates forget this as soon as we stand up and begin lecturing. For example, we’d appreciate it if students didn’t sit there and talk through lectures. If people are talking it makes it hard for everyone else to hear, and it’s extremely distracting (yes we can see you wherever you sit even in the huge lecture halls). It’s also really rude. Imagine how you would feel if someone did the same thing to you. We understand that some people might not be interested in the topic or have something urgent to discuss with a friend, but if that’s the case please don’t do it in the lecture.

We also work really hard to make our lectures interesting and informative. There is nothing more soul crushing than a student saying how rubbish your lectures are after you’ve spent days writing them, adding interesting anecdotes and trying to deliver them with enthusiasm. Of course we know not everyone is interested in the same things, but try to make negative feedback constructive so we can improve things for next year and don’t just get depressed about it!

2. Learning is a two-way process

Learning is a two-way process, so you have to be involved, especially if you want to shape the content of the lecture course. Generally, we are amenable to pausing and running through material again, in different ways if you don’t understand something. We can only do this if you are there, and if you ask a question. Complaining in feedback that the lecture notes or slides weren’t detailed enough implies you probably weren’t there in the first place to fill them in. Of course it’s hard to ask questions in large lectures, but feel free to ask us at the end of a lecture, during a practical or by email. Some of us are even amenable to being asked questions via Twitter! During the lectures/tutorials/practicals you have our almost undivided attention: this is the time to ask all your questions, not the week before exams when you are panicking and we are busy doing our other jobs (see 3 below).

3.Teaching is only part of our job

Our jobs as academics are a lot more than teaching. We also supervise Masters and PhD students, apply for research funding, perform research, write papers, review other people’s papers before they are published, go to scientific conferences and present our work, teach other scientists at workshops and run large parts of the University through administrative roles we undertake. And teaching isn’t just writing lectures and delivering them, we also have to write exams, mark exams and coursework, organize timetables and practical materials, instruct the demonstrators, and put things onto Blackboard etc. This (and see also point 4 below) is why we can’t always meet you when you’d like us to, or reschedule lectures/practicals to suit you, or necessarily offer ad hoc tutorials just before the exams. We’re generally juggling a million different tasks so although the change may seem minor to you, it could throw out our quite rigid schedules.

4.We have lives outside the university.

Not only are we very busy when we are at work, but we all have lives outside the university. We have kids who need to be picked up from school, put to bed, and looked after when they’re sick, we have partners who would like to spend time with us, we have friends, families, pets, hobbies and TV shows we like to watch in our pajamas. So please don’t get cross when we can’t give you feedback on your essay as quickly as you’d like (and don’t look quite so horrified on the occasional evenings that you bump into us in the pub!). Please note this means that if you hand something in on a Friday night, it is unlikely to have been marked by the Monday morning, as we also (occasionally) don’t work all weekend. Like everybody else, we officially work only in the working week.

5. We do not get the whole summer off from work

This follows on from point 2. Because a lot of our work actually has nothing to do with undergraduate student teaching, lecturers do not get the whole summer off work. This summer I have taken two weeks off and have worked a normal 8 hours a day schedule, rather than staying until late most nights like I do in term-time. I have also presented my work at two conferences, attended another two conferences with our PhD students, written two scientific papers, worked on two other papers, supervised a Masters thesis project, prepared work for my new intern, supervised my PhD students, and run three different workshops in Ireland and the UK. I have also been preparing my teaching for the term!

Authors

Natalie Cooper and Andrew Jackson (Assistant Professors at TCD) ncooper[at]tcd.ie, a.jackson[at]tcd.ie

@nhcooper123 @yodacomplex

Image source:
readingforall101.blogspot.ie

20/09/201317/09/2013

The ‘Natural’ World

What images come to mind when you think of a field ecologist? Do you see what I see? I see someone, probably in khaki shorts and a broad-brimmed hat, walking through thick rainforest, listening to the calls of birds, waving off insects determined to find a patch of skin to bite, and smelling the exotic aromas of plants and animals living, dying and decaying.

You may well be thinking that this is an idealised image of a field ecologist and while it may have been true 50 years ago, it’s harder to imagine now. After all, every day we hear about habitat destruction and how mankind is damaging the natural environment. But I’d like to propose that even 50 years, or 100 years, or even 1000 years ago mankind was having an impact on the environment and this idea of the ‘natural’ world really needs rethinking.

Take, as an Irish example, the Burren. I visited this area for the first time a few weeks ago and was stunned by the rugged beauty of the place. It was sparsely populated, only a few sheep and cows (and the occasional donkey) provided evidence of any human presence in places; how much more ‘natural’ could one get? Plenty more, it turns out, as the entire landscape is the result of human impacts.

The entire area is littered with signs of prehistoric people, the most striking of which was the 5,000 year old Poulnabrone portal tomb. This tomb dominates a limestone pavement with a view that stretches for miles across to the sea. Yet reading the information boards it quickly became apparent that this was not the landscape in which the tomb was constructed. At that time the area was heavily forested with small clearings made by people to farm and build their homes. The tomb would most probably have been largely hidden from all but those who knew its location. Yet over the next few thousand years people cut down more and more trees to make use of the timber and to clear the way for more farmland. However, the trees were the only thing holding the thin soil in place and with the loss of the trees, the soil soon followed, until all that was left were patches of vegetation and entire hillsides of exposed limestone bedrock. That stunning ‘natural’ landscape is the result of ancient habitat destruction!

A similar story can be told across much of the world. New Zealand, adopted home of the hobbits, with its fields and rolling hills, was once almost entirely forest. Yet when the Maori reached the islands around a thousand years ago they proceeded to reduce the forest cover by almost half, and the European settlers reduced it by half again. In addition, the loss of so many endemic species also led to changes in the structure of the remaining forests, though precisely how is still being debated.

It’s the same the word over. Take, as a final example, Australia. The sixth largest country, the world’s largest island, yet it has only 0.33% of the world’s population. Surely humans can’t have had much of an impact there? Well, yes they can, particularly if you think that they are at least partly responsible for the loss of the megafauna. For more details on that I highly recommend Tim Flannery’s 1994 book ‘The Future Eaters’, with the teaser that I never knew that dung was so important to a properly functioning ecosystem! But even ignoring that, Aborigines had a long and close association with the land, heavily modifying environments through activities including the use of controlled burning.

I could go on (and on, and on) for every habitat on almost every continent, but it would get rather monotonous. My point is that when we look at the ‘natural’ word we rarely see something that’s never been touched by man however far into the ‘wilds’ we go. The ‘natural’ world has been modified, sometimes subtly, sometimes dramatically, for thousands of years as countless generations have struggled to survive and prosper. Ecology, however much we like to think otherwise, always involves a human component. Sometimes the humans who made the impacts have long gone and the landscapes have become so normal and ‘natural’ its hard to think there was a time they were ever different. But if we are to understand the world we need to understand the historic impacts we have had, not just on climate, not just in towns and cities, but also on the ‘natural’ world.

Author

Sarah Hearne: hearnes[at]tcd.ie

@SarahVHearne

Image sources

Sarah Hearne

Ewers et al. (2006) Biological Conservation 113:312-325

01/07/201301/07/2013

Why dating a scientist has ruined my life

Did you know that otter’s penises are shrinking? I didn’t. Until I was informed of that by my scientist girlfriend. I can no longer look at otters the same way again. Science ruins everything.

I used to enjoy life. The future promised to us by Back to the Future was so close! That all ended the day I started going out with a scientist.

I’m now a cynic. I don’t trust anything that isn’t peer reviewed and even then, what’s the impact factor of the journal? I even know some journals by name now! About 50% of the time I can say “Congrats on getting published in PNAS” without laughing.

Nights out with scientists are different to nights with any other group of people. While most people like to leave their work behind them, scientists take theirs with them and just get slightly louder while they discuss it. It must be how Robin Ince feels when he goes for dinner over at Brian Cox‘s, but instead of talking about the Higgs Boson the topics range from the plight of the buff tailed bumblebee to dinosaur biomechanics. Who knew dinosaurs could be so boring? I didn’t. Until I started dating a scientist.

Peer review is a twisted system. It’s a place where people can be just downright mean to others and get away with it. It seems that the point of peer review is not just to ensure that only the best research gets published in the best journals, but to make those whose work isn’t good enough feel stupid and embarrassed that they thought their puny intellect was capable of appearing in a journal as glorious as the almighty [redacted]!

I must admit, it hasn’t ALL been bad, I no longer think everything gives me cancer (who knew The Daily Mail wasn’t a reliable source?!) That’s right, this blog PROBABLY won’t cause cancer.

I now look forward to being told that my blog doesn’t ask a question, didn’t have a hypothesis and had no supporting data. I haven’t even cited anything. I’m ok with those inevitable criticisms. If they get me down I just have to keep reminding myself, only two more years until we get hoverboards.

Author

David Fortune: davidfortune23[at]gmail.com

Photo credit

Wikimedia Commons