Field Course 2009 – Not Just Sea Fret

What can you learn on a field course? That grouse fly at 80 miles per hour? That there are about 4100 dog whelks on Runswick Bay beach? That even in June you need to pack heavy duty waterproofs when carrying out fieldwork in North Yorkshire?

The field course is over for another year and, despite the sea fret that accompanied it, it was a resounding success. Let’s start at the beginning…

Danby Moor is a short drive from the field center and set the tone for the rest of the weekend. Despite the weather the students threw themselves into the task of studying moorland management. Random sampling of the vegetation at various stages of recovery from burning showed secondary succession on the moors. As this succession is never allowed to continue to the climax community of woodland we call the moorland a plagioclimax, forever frozen at the serial stage that most benefits its human owners. In this case a patchwork of heather which provides the food and shelter for grouse, and many other species of birds and mammals besides. The chi² statistical analysis showed variation in the vegetation between the three burn sites, although a more in depth investigation would be needed to confirm this observation.

Saturday morning started with invertebrate sampling using sweepnets and pooters. The dew on the grass did not help when the nets soon became soaked and most grass dwelling insects must have retreated to drier areas. Still we found a variety of insects, a few spiders, and even a dead mole (though not through use of the sweepnet of course!). The beating tray collected more invertebrates from the trees and the pooters were put to good effect again. And although we put out various traps without much success, I think the point was made that sampling mobile organisms can take many forms depending on the organisms being targeted.

So then the trip to Runswick Bay for rocky shore ecology. We started with mark-release-recapture of Dog Whelks on a section of the rocky shore. I didn’t quite expect to find so many, but 564 molluscs collected in 5 minutes is pretty good going. A few minutes later and each one had a white dot on its shell to identify it as having been caught. The whelks were released back into their environment to to mingle with their undiscovered cousins. We would return the next day to hunt them out again…

We sampled zonation on the rocky shore using an interrupted belt transect. To speed things up we used the ACFOR scale to record the abundance of the various seaweeds and counted the animals individually. Back in the lab the kite diagrams showed the distribution of the organisms on the rocky shore and the effect of the abiotic factors on zonation. A Spearmans Rank Correlation Coefficient statistical test showed a significant correlation between bladder wrack and distance from high tide, although there were enough anomalies in this correlation to question the validity of the data. More data is needed to increase confidence in this relationship.

The next day we ventured to Coatham Sands in Redcar for sand dune ecology. Clearly the lack of sleep was catching up with people as the usual enthusiasm for the mighty Marram grass was not evident in the group, despite one teachers clear admiration for its xerophytic adaptations. The aim was to find evidence of primary succession, which occurs as colonising organisms affect the abiotic environment allowing other organisms to grow and out-compete the original plants in an area. This should eventually result in a climax community of trees, but this does not happen in Redcar as the rear of the dunes is put to use as industrial land. Still, the science of succession was evident in this industrial landscape showing that nature persists in all but the harshest environments.

It should be noted that the final evening’s rounders match saw a convincing win for the Snape-Haye team against the frankly disappointing Howell-Eastwood team. Clearly better biologists than rounders players, the returning sea fret was a suitable excuse for a poor batting/fielding display.

All, then, was over apart from the write-up on the last morning. This took the form of a sand dune profile  and line graphs showing how species changed along the dune. This representation of the data showed patterns of distribution more clearly than tables of data could, and was worth the effort I think.

So what do you learn on a biology field trip? The process of succession and effects of abiotic factors, the reasons for zonation on the rocky shore and the associated change in plant and animal life, the different methods of animal sampling and the limitations of these, the use and application of statistical testing to make sense of data that does not fit a perfect pattern. All of this. And also that Biology is the study of life, and life has to be investigated where it is found. Outside. Where sometimes it is wet, and sometimes it has sharp edges, but more often than not it is simply stunning.

Thanks to the students for making the trip so successful, the field centre for providing us with great accommodation and fantastic local knowledge, and the teachers who put so much effort into making this weekend a success.

Ethical Aspects of Fieldwork

The catch 22 predicament of studying natural habitats is that simply by entering the habitat you will be affecting it. Humans, being big, loud and smelly (or perfumed, if you prefer) will inevitably alter the behaviour of the wildlife and may leave the habitat in a different state than it was found in. This is, to some degree unavoidable, but the impact can be minimised by considering your potential habitat and ways in which you may affect it.

On the field course we will be sampling grassland invertebrates, rocky shore organisms, sand dunes vegetation and potentially mammals (if we can trap any!). To do so ethically requires planning. The following organisations have codes of conduct for fieldwork. Take time to read them.

The Marine Conservation Society seashore code

The Wild Flower Society code of conduct

The Amateur Entomologists’ Society code of conduct for collecting insects and other invertebrates.

Discovering the beauty of  natural habitats is one of the best things about being an ecologist. We need to do our best to leave our study sites, and the animals living in them, in the best, most natural, state possible.

Field Course 2009

This years field course is fast approaching. 26th to 29th June 2009.

All students planning on continuing into A2 are expected to attend the field course. Fees need to be paid by 19th June at the latest, so if you have paid your deposit you need to get the final installment in by the end of next week. If you have yet to pay anything, you can pay in full by the 19th June. If you think there will be problems finding the money, or problems attending the course, you must speak to a member of the Biology team as soon as possible so that we can make arrangements.

This years course has been redesigned to suit the new specification so you can be sure that what we cover in the field will be useful in the exam hall in January.

It will also be fun and, I’m assured, it will be sunny also!

Maybe…

The Prince Philip Award and Marsh Prize 2009

I’ve been looking out for this for a while. The Prince Philip Award and Marsh Prize is an annual competition for students aged 19 years or younger. To quote the organisers, ‘The entry should be a written account of original practical work involving some aspect of animal biology, e.g. behaviour, physiology or ecology.’

The purpose is to encourage students to get on with investigating biology rather than just learning it from books, or lab practicals.

Rules and guidlines are here. Come and speak to a member of the biology staff if you would like to enter the competition for guidance on project ideas. It would be a great way to extend your biology learning experience, and should be interesting and fun to do also.

Royal Society Prize for Science Books

It was about this time last year that I began putting together a ‘further reading’ list for A level biologists. It was to be included in the ‘welcome booklet’ that we gave the year 12’s at the start of the year. The task was harder than you might expect. It’s easy to find good books about genetics and evolution, but other aspects of biology just don’t get written about that much. Surveying the biology teachers at school found that we had, more or less, all read the same books (these were therefore included in the list), but finding a range of books to list that we knew were good was worryingly difficult.

It’s a shame that I did not know about the Royal Society Prize for Science Books. I do now. ‘The world’s most prestigious award for science writing’ (their words, not mine) have published their longlist for this year’s award, and it makes for interesting reading.

I have to admit, I have only read one of the books on the list, the rather fabulous ‘Bad Science’ by Ben Goldacre. It’s good enough to make it onto next years further reading list. But I’m ashamed to say I haven’t even heard of any of the other books, yet alone read any of them! So, as a committed scientist, I plan to read at least one of the books on the list. I’ll be reading ‘The drunkard’s walk: How randomness rules our lives’, by Leonard Mlodinow. I’ll let you know how it goes!

The shortlist will be announced on 25th June 2009, and the winner on 15th September 2009, so you may prefer to wait until then to pick one. But do pick one! I’d love to hear from anyone who has read any of these books and could give me a review of it. If it’s good enough I’ll let everyone know.

Conjugation

Some of us have been creating strains of resistant bacteria. No, this isn’t through lack of personal hygiene, we’re all much too clean for that sort of thing. Instead we have been producing the conditions suitable for bacterial conjugation in the lab in an experiment provided by Survival Rivals.

The experiment was an all round success (of course!). We took two strains of bacteria, each resistant to a particular type of antibiotic. We then ‘mated’ the two stains by putting them together in a nutrient broth and leaving them at 30°C for 24hrs. Next, we streaked the bacteria onto nutrient agar which had been inoculated with antibiotics and left this over the weekend. The results showed some bacteria had gained resistance to both types of antibiotics, which could only have been as a result of bacterial conjugation where the resistant plasmid from one strain of the bacteria had been passed into the other stain of resistant bacteria. This was shown by colonies of this ‘dual resistant’  bacteria being able to grow on agar plates with both types of antibiotic present.

The Survival Rivals website has lots of additional information on this experiment, including an animation of bacterial conjugation.

Manchester University have produced a series of videos on aseptic technique, some of which we watched in preparation for this experiment. They’re all here.

So, thanks to the Survival Rivals team for providing the experiment and well done to the students for completing it successfully.

Now, wash your hands.

Replication of DNA

Before cell division can take place DNA has to be copied. It needs to be copied in such a way that there are no mistakes so the new strand of DNA is identical to the original. The process through which this is achieved is Semi-conservative replication.

Semi-conservative replication works on the principle that the organic bases in DNA fit together in complementary pairs (adenine is complementary to thymine, cytosine is complementary to guanine). So DNA can be copied by separating the two strands and then building up a complementary strand based on the bases on the original strand. In this way you get two DNA molecules which will be identical to each other as each strand has a new complimentary partner. It is called semi-conservative because the new molecules contain one of the original strands and one new strand, so half of the original DNA molecule has been conserved in this new one.

You need to know the process of semi-conservative replication including the roles of enzymes in the process. You should, of course, use your course book and the books in the library to learn this, but there are also animations here, here and here which might help you visualise the process.

It’s also important that you take time to consider how evidence was gathered to support this theory of replication. A good written explanation is here, whilst good animated explanations are to be found here and here.

As always, if you find any other good links to ideas covered in this post then please feel free to add a comment and share your find!

Meiosis

We now move onto meiosis. Meiosis is a way of producing new cells. Different to mitosis, which results in genetically identical cells, meiosis produces four cells that have only half the number of chromosomes as the parent cell and are genetically unique. This is how gametes are produced. Gametes need to have half the number of chromosomes as a normal body cell (somatic cell) because when two gametes fuse the fertilised egg cell will end up with a full set of 46 chromosomes, 23 from each gamete.

How gametes are produced, and how genetic variation in gametes come about can be read about on pages 140 -143 in the course book. There are good animations of meiosis here, here and here. Don’t worry too much about the terminology – we come back to this when we study mitosis later.

Darwin

Charles Darwin was born two hundred years ago this month (12th Feb 1809). He is one of the most important and influential Biologists of all time. He published his most famous book ‘On the Origin of Species’ 150 years ago this year, and revolutionised scientific thinking.

The BBC are celebrating the anniversary of his birth through a series of programmes. On Sunday they showed a fantastic program presented by David Attenborough called Charles Darwin and the Tree of Life. If you missed it you can watch it on the BBC iPlayer here.

Also worth watching on the iPlayer is a programme called What Darwin Didn’t Know. It’s here, but not for much longer!

The Open University are doing lots of things also for Darwin’s Anniversary. Go to www.open2.net/darwin.

Instructions in Question Papers

Good luck to all of the Biologists sitting exams over the next few days. Remember that staff are available for any last minute clarifications you may need. All you need to do is ask. We don’t mind!!!

As a last minute piece of advice I would encourage all students to make sure they read the questions carefully and answer the question as it is asked. Explain when it asks you to and describe when it says ‘describe’. Its very easy to drop marks by confusing the ‘trigger’ words. Click here for a pdf from AQA that explains all of the instructions that could appear in the questions.