Saturday, 29 January 2011

The Thin Evolutionary Line

A lot has been mentioned recently of the article "Defeating Creationism in the Courtroom, But Not in the Classroom" (Berkman & Plutzer, 2011).

The main quoted criticism is that, among teachers in the USA there is "a pervasive reluctance [...] to forthrightly explain evolutionary biology". Slightly fewer than one in three teachers were considered to be "effective educators" in evolutionary biology, described thus:
"They unabashedly introduce evidence that evolution has occurred and craft lesson plans so that evolution is a theme that uniļ¬es disparate topics in biology."
While the study was carried out on American teachers, this ratio seems reasonable to me - the overwhelming majority of my science department is creationist in nature, which I expect is a barrier to effectively educating students about evolution (am choosing my words carefully...).

I try my hardest to do a good job when teaching evolution. I try not to make a big deal out of it, and treat it like any other branch of biology (which it is), teaching it from a position of authority as though it was the Krebs Cycle. Mostly, a matter-of-fact approach is effective. However, all it takes is for a student to say "Yeah but you don't really believe this, right miss?", and the class instantly degenerates into a discussion of religion and philosophy, while I feel like I'm struggling to hold it together and return to science.

Add into the mix the common interpretation of Equality and Diversity Guidelines:
"Acknowledging diverse cultural backgrounds enables learners to bring their own life experiences to the classroom"
is usually interpreted as:
"So as not to hurt the feelings of the students whose creation narratives exclude evolution as a valid explanation, make sure you stress that evolution is only a theory and that lots of groups have different views of the origins of species."
And having seen a colleague's Scheme of Work, this is only marginally paraphrased from the actual E&D notes.

This is starting to bother me, as I am researching effective teaching methods for evolution, and one of my PGCE lecturers is a little too keen that I treat evolution as being just another philosophical viewpoint, rather than a very well supported scientific fact. How do I do evolution justice in my classes without being perceived as being bombastic, not taking into consideration students' diverse backgrounds, or "forcing" my "beliefs" onto impressionably young minds?

I want to be "unabashed" in my teaching of evolution, but I am also afraid of complaints from students and criticism from colleagues. And that is a rotten situation to be in.

Berkman, M.B. & E. Plutzer. 2011. "Defeating Creationism in the Courtroom, But Not in the Classroom. Science 301: 404-305. DOI:10.1126/science.1198902.

Monday, 24 January 2011

They Don't Buy It

Today I discussed endosymbiosis with my AS Biology class. It's probably one of the most fascinating aspects of cell biology. There are three major similarities between mitochondria and bacteria: their membrane, their DNA and their method of reproduction. It is perhaps one of the most elegant theories in biology, and I find the evidence utterly compelling.

I drew this, so don't you dare copy it...

But the majority of students utterly rejected it. Now, I've been spoilt so far - my A2 students are mostly heathen and proud of it, last year's GCSEs barely had to look at anything more taxing than horse evolution, and the BTEC students don't have to learn a damn thing about evolution, natural selection or speciation.

So some of the gems I got today included:
"I accept it, I just don't believe it."

"You can prove collision theory. You can't prove evolution."

"Are gorillas going to evolve into humans?"

"This is rubbish!"
My responses, in order, were along the lines of "I don't want you to believe science, I want you to accept science, so that's fine by me.", "You can only prove mathematical theories - for all you know there are tiny elves living in chemicals who get really angry and throw atoms at each other when you heat up the solution.", "No." and "Tough, it's on the specification." These probably didn't convince anyone (although I am particularly proud of the collision theory elves).

So I'm starting to think of all the other topics I've taught them since the start of the year, and I'm wondering how much else in biology has as much/little supporting evidence as endosymbiosis, but is still entirely accepted by my students. As far as I am aware, the evidence for endosymbiosis is pretty good - it's been observed by Kwang Jeon in amboebae. Mitochondrial cristae seem to be homologous to prokaryote mesosomes. On the other hand, the last thing I heard is that the six-carbon immediate product of carbon dioxide and ribulose bisphosphate in the Calvin cycle is so unstable that it has not been identified yet. And the enzyme responsible for photolysis of water in the light-dependent reaction may or may not be one of the photosystems, according to a recent paper, but they absorb what I do teach them in this regard as gospel.

These students seem happy enough to accept a 4.6Ga old Earth. Most of them are satisfied with the Big Bang, and all of them are just fine with gravitational theory, collision theory and the kinetic theory of gases. It looks like I have an uphill battle, and I'm a little apprehensive about the prospect of teaching evolution and natural selection to them. I've also realised (naïve though I may have been) that there is very little chance of me convincing them of the evidence for any aspect of descent from a common single-celled ancestor, or any of the cool stuff in between that and the present day.


Thursday, 20 January 2011

Treasures In Old Books

Several years ago, while at Washington University in St Louis, I headed to the Biology department library to return some books. As many libraries are wont to do, they were chucking out old copies of books, and looking through the pile I managed to score a few classic texts, including Lynn Margulis' "Early Life". Astoundingly, tucked inside, was a photocopy of a letter sent to Lynn on 2 June 1982 (the letter is typewritten, and the photocopy seems to have been made not long after and has a handwritten note by Lynn in the top corner).

The letter reads:
Dear Lynn,

I have now read Early Life with pleasure and education.

It is interesting that this started out as one of the proposed Scientific American books envisioned by Gerard Piel and originally under the supervision and editorship of Edward Immergut. I, too, started a book for that series. As you of course know, Piel sacked Immergut. He then proposed to do the editing himself, found he couldn't do it, and then released or reassigned those under way. Yours went off to Science Books International, a firm I do not know. Mine went to W.H. Freeman & Co., which no longer has any connection with Bill Freeman, a geologist and old friend of mine, but is an affiliate of Scientific American. (It is not 100% clear which one owns the other, but they are essentially the same outfit, one publishing magazines and the other books.) My book for them is [title removed for reasons which shall become apparent] and is scheduled for November, 1982.

Gerry Piel's original idea was to have books on branches of science written by specialists for other scientists not specialized in the same field. Your book does a beautiful job of that sort, although it will in some spots be rather slow reading for a scientist who is not specifically a biochemist.

I will mention just a couple of quite minor points, if only to show you that I have read your book word for word. For example on p. 72 you give 3.5 billion years as the age of the Warrawoona fossils but in a footnote recommend the utmost caution because the age might only be 70 million years. If that is a possibility I do think we should skip the Warrawoona things until they are better tied down. Of course there were similar prokaryotes 70 million years ago (as there are today) but at that time there were also mammals and other very advanced eukaryotes.

Another point even more trivial is that on p. 9 you say that "dogs, cows, giraffes, horses, and even human beings" all have five fingers or toes on each limb. Human beings do, but none of the others you name do. (Their ancestors did, but that isn't what you say.)

As you may recall, I was at first rather dubious about your theory of the origins of organelles from symbionts. You have now convinced me that this has often been correct. Some of your suggestions do still seem somewhat dubious, but you also leave room for some doubts.

Congratulations on a fine book.
Now, who do you think wrote that letter? I removed the title of the book from the letter to try and get some more interesting guesses out of you (since a straightforward google search would have thrown up the author immediately). Nothing but bragging rights for you, but give it a go. I'm looking forward to reading your guesses.

I will be covering endosymbiosis with my AS biologists next week, so I shall be re-reading "Early Life" again over the weekend, I think.

Tuesday, 18 January 2011

Research In A Different Direction

I have fairly conclusively demonstrated that I have absolutely no talent for palaeontology (if I had any talent for it I would be heading towards tenure by now, rather than lecturing in further education). But what I do seem to do pretty well is teach palaeontology and evolution. Those who can't, teach? Maybe.

I am currently in my second year of a two-year part-time PGCE (Postgraduate Certificate in Education), and one of the assignments I have to complete is a research paper on a topic relevant to our teaching, whether subject-specific or pedagogical. For some time I have been intrigued about the different creation narratives of various religions, and how that affects students' acceptance of evolution. Anecdotally, I have noticed the most resistance to evolution from my First Diploma Applied Science students (vocational qualification equivalent to GCSEs), and the most acceptance of evolution from my A2 Biology students. Which is certainly preferable to the inverse. And so far the only students to have directly challenged me in the course of teaching evolution have been those whom I believe to be at least culturally Christian or Muslim.

Incidentally, when discussing the age of the Earth at 4.6 Ga, one of my Hindu A2 students rolled his eyes and sighed "Pffft, young earth creationist", before he could no longer keep up the straight face and dissolved in giggles.

Much of the anti-creationism material, literature, resources and guidance available to educators seems to be aimed towards objectors from the Abrahamic religions. While these certainly account for a large number of potential creationists, there are still the Indian, Taoic and Iranian religions to examine, not to mention more modern and folk religions. The religions represented in my classes are (in descending order of proportions): Islam, Sikhism, Hinduism, Christianity and Buddhism, so I really must take account of the non-Abrahamic faiths.

I hope to identify whether a change of strategy is needed when teaching evolution and palaeontology to non-Abrahamic religious students. I plan to read up and give myself a much better idea of the creation narratives (I'd love to say myths, but I'm trying to be a little less strident in my atheism - it doesn't seem to be an attractive trait in a trainee lecturer). I'd like to feel more confident teaching evolution to non-Christian students who are struggling to reconcile their faiths with science. And I would love to learn something useful and publishable, but I don't hold my breath.

If nothing else, my wasted years of supposed PhD study have served to make me feel much more confident with research than my fellow PGCE students, given me a better grip of primary literature, and enabled me to do Harvard referencing blindfolded with my hands tied behind my back. So it wasn't all in vain after all.

Thursday, 6 January 2011

MYRSFO: Scottish Qualifications

I assume that, if I had studied in Scotland and was training to teach Scottish qualifications, I would find these far less bewildering than they actually are. Fortunately, I happen to be married to a Scotsman who has been very helpful with translating for me. Rather than specifications, the list of criteria is referred to as the arrangements on the SQA website.

Standard Grade
There are general and credit levels within this (broadly equivalent to foundation and higher tiers in GCSEs), but for the sake of getting the information down, I've combined the two.
  • State that competition occurs when organisms have a need for the same resources
  • Describe some effects of competition
  • State that a species is a group of interbreeding organisms whose offspring are fertile
  • State that variation can occur within a species
  • Give examples of continuous and discontinuous variation
  • Explain what is meant by continuous and discontinuous variation
Now, what has shocked me is that at Standard Grade, there is absolutely no mention of evolution or natural selection. There is brief mention, in topic 3b, that "Pupils should be aware that selection favours those individuals that leave most surviving offspring. This sub-topic provides opportunities for pupils to investigate ways in which animals achieve this through sexual reproduction". But that is really not good at all. Paul has suggested that evolution might be covered earlier in the curriculum, during general science, but that's not really an excuse.

The Intermediate 1 and 2 qualifications listed are, I understand, more vocational in nature, and as such because I've excluded BTEC and applied science courses for the rest of the UK, I'll exclude them here too. There are some aspects of evolution included in Intermediate 2, which serves to reassure that the Powers That Be do not think that evolutionary biology is only useful to those destined for university.

Highers are equivalent to A-Levels (give or take), and are taken over one year, as far as I am aware.
  • Natural selection:
    - The survival of those organisms best suited to their environment
    - The concept of the species
    - The importance of isolating mechanisms as barriers to gene exchange leading to evolution of new species
    - Adaptive radiation
    - The high-speed evolution of organisms such as antibiotic resistant bacteria and the melanic peppered moth
    - The conservation of species through wildlife reserves, captive breeding and cell banks. The maintenance of genetic diversity
There are some small bits about succession as well, but the majority of the relevant bits are covered in the module on variation and adaptation.

Advanced Higher
Back in the Jurassic period, these were Sixth Year Studies, and students took them in their final year, usually with another couple of Highers for good measure. Since neither Paul nor I really know what these are all about now, so more recent Scottish school leavers feel free to comment. Not all schools would have offered all the SYS subjects, so it is possible that this is still the case.
  • Analysing the genomes of other species. Comparison of the human genome with other species reveals remarkable similarities
  • Biotic interactions:
    - Distinction between biotic and abiotic components of ecosystem; density-dependent and densityindependent factors. Interspecific and intraspecific interactions
  • Predation:
    - Predator/prey population cycles. The role of predators in maintaining diversity in ecosystems by reducing the population density of prey species allowing weaker competitors to survive
    - Defences against predation; camouflage (crypsis and disruptive coloration); warning (aposematic) coloration. Batesian and Mullerian mimicry
  • Competition:
    - Exploitation competition and interference competition. The concept of fundamental niche as a set of resources a species is capable of using. Realised niche as the set of resources actually used due to competition. Resource partitioning. The competitive exclusion principle
  • Symbiosis:
    - Parasitism
    - Commensalism
    - Mutualism
  • The costs, benefits and consequences of interactions
  • Changes in complexity of ecosystems
    - Autogenic succession (primary and secondary succession). The increase in complexity of ecosystems from pioneer through to climax communities. Facilitation of change in early stages. Increase in complexity shown by increase in: diversity of species, variety of habitats and niches, complexity of food webs. Changes in stability and productivity through succession
    - Reference to effects of external factors in allogenic succession and relatively short-term nature of degradative (heterotrophic) successions
  • Evolution of behaviour:
    - Natural selection of behaviour patterns
    - Single gene effect on behaviour
  • Feeding behaviour:
    - Predation strategies
    - Foraging behaviour
    - Defence strategies
  • Sexual behaviour:
    - Male and female investment
    - Courtship and display
Those readers in Scottish universities, this is an absolute gift - almost all aspects of palaeontological research can be related to the specification for Advanced Higher, so knock yourselves out there. I wish that the A-Level specifications had half of this detail, as in my humble opinion this is way more fun and interesting than considering the ethics of performance-enhancing substances.

Wednesday, 5 January 2011

MYRSFO: A2 Biology

By A2, the students should be able to deal with some quite high-level research, and read some straightforward scientific papers. They have probably carried out some ecological fieldwork, so are used to the particular issues raised by sample size, data collection, and trying to do science in horizontal rain (why there isn't more uptake for earth science degrees, I do not know).

Unit BIOL4
  • Succession from pioneer species to climax community
  • At each stage in succession, certain species may be recognised which change the environment so that it becomes more suitable for other species
  • The changes in the abiotic environment result in a less hostile environment and changing diversity
  • Species exist as one or more populations
  • The concepts of gene pool and allele frequency
  • The Hardy-Weinberg principle. The conditions under which the principle applies
  • Differential reproductive success and its effect on the allele frequency within a gene pool
  • Directional and stabilising selection

Unit A2.1
Students should be able to:
  • Understand how populations grow
  • Distinguish between r- and K-selected species
  • Understand the ways in which populations may interact
Unit A2.2
Students should be able to:
  • Understand the concept of the gene pool
  • Understand the Hardy-Weinberg equation and apply it to calculate allele and genotype frequencies in an outbreeding population
  • Understand selection and its contribution to the maintenance of polymorphic populations and evolutionary change in populations
  • Understand the concept of species and the process of speciation

Unit 4
Students will be assessed on their ability to:
  • Describe the concept of succession to a climax community
  • Describe how evolution (a change in the allele frequency) can come about through gene mutation and natural selection
  • Explain how reproductive isolation can lead to speciation
  • Describe the role of the scientific community in validating new evidence (including molecular biology, eg DNA, proteomics) supporting the accepted scientific theory of evolution (scientific journals, the peer review process, scientific conferences)
  • Describe how DNA profiling is used for identification and determining genetic relationships between organisms (plants and animals)

Unit F215
Candidates should be able to:
  • explain why variation is essential in selection
  • use the Hardy–Weinberg principle to calculate allele frequencies in populations
  • explain, with examples, how environmental factors can act as stabilising or evolutionary forces of natural selection
  • explain how genetic drift can cause large changes in small populations
  • explain the role of isolating mechanisms in the evolution of new species, with reference to ecological (geographic), seasonal (temporal) and reproductive mechanisms
  • explain the significance of the various concepts of the species, with reference to the biological species concept and the phylogenetic (cladistic/evolutionary) species concept
  • explain, with examples, the terms interspecific and intraspecific competition

Unit BY5
  • Genetic and environmental factors produce variation between individuals
  • Variation may be continuous and discontinuous; heritable and nonheritable. Inter and intra-specific competition for breeding success and survival
  • Selective agencies (e.g. supply of food, breeding sites, climate). The gene pool and genetic drift
  • Selection can change the frequency of alleles in a population
  • Isolation and speciation
  • Separation of populations by geographical, behavioural, morphological seasonal and other isolation mechanisms. Hybrid sterility
  • Darwin's theory of evolution that existing species have arisen through modification of ancestral species by natural selection
  • Principles of succession as illustrated by the change from bare rock to woodland
  • Use of terms primary and secondary succession, pioneers, sere and climax community
A2 Biology is much more concerned with ecology, speciation and reproductive isolation. Some new examples of evidence for speciation, co-evolution of parasites, or even a tame scientist with a collection of cichlid fish, will go down very well indeed.

Tuesday, 4 January 2011

MYRSFO: AS Biology

After the somewhat vague and bewildering GCSE specifications, we settle down a little with the post-compulsory qualifications. A-Level is divided into two: AS and A2. It seems natural to stick with this division here, and to go with AS Biology first.

Unit BIOL 2
  • Candidates should be able to analyse and interpret data relating to interspecific and intraspecific variation
  • Candidates should appreciate the tentative nature of any conclusions that can be drawn relating to the causes of variation
  • The principles and importance of taxonomy
  • Classification systems consist of a hierarchy in which groups are contained within larger composite groups and there is no overlap
  • The phylogenetic groups are based on patterns of evolutionary history
  • A species may be defined in terms of observable similarities and the ability to produce fertile offspring
  • One hierarchy comprises Kingdom, Phylum, Class, Order, Family, Genus, Species
  • Candidates should be able to appreciate the difficulties of defining species and the tentative nature of classifying organisms as distinct species
  • Courtship behaviour as a necessary precursor to successful mating. The role of courtship in species recognition
  • An index of diversity describes the relationship between the number of species and the number of individuals in a community

Unit AS.2
Students should be able to:
  • Understand that organisms are adapted to their environment
  • Understand that ecological factors have an influence on the distribution of organisms
  • Understand the role of selection in maintaining the adaptiveness of populations of organisms in their environment
  • Understand that biodiversity involves variation among living organisms at all levels of biological organisation
  • Measure species diversity and appreciate that genetic diversity can be measured
  • Understand the principle of taxonomy
  • Understand the concept of the species
  • Understand the other taxa within which species can be grouped
  • Understand phylogenetic taxonomy as a means of classifying sets of species according to ancestral relationships
  • Appreciate the five kingdom system of classification

Unit 2
Students will be assessed on their ability to:
  • Explain the terms biodiversity and endemism and describe how biodiversity can be measured within a habitat using species richness and within a species using genetic diversity, e.g. variety of alleles in a gene pool
  • Describe the concept of niche and discuss examples of adaptation of organisms to their environment (behavioural, physiological and anatomical)
  • Describe how natural selection can lead to adaptation and evolution
  • Discuss the process and importance of critical evaluation of new data by the scientific community, which leads to new taxonomic groupings (i.e. three domains based on molecular phylogeny)
  • Discuss and evaluate the methods used by zoos and seedbanks in the conservation of endangered species and their genetic diversity (e.g. scientific research, captive breeding programmes, reintroduction programmes and education)

Unit F212
Candidates should be able to:
  • define the terms species, habitat and biodiversity
  • explain how biodiversity may be considered at different levels; habitat, species and genetic
  • define the terms classification, phylogeny and taxonomy
  • explain the relationship between classification and phylogeny
  • outline the binomial system of nomenclature and the use of scientific (Latin) names for species
  • discuss the fact that classification systems were based originally on observable features but more recent approaches draw on a wider range of evidence to clarify relationships between organisms, including molecular evidence
  • define the term variation
  • discuss the fact that variation occurs within as well as between species
  • describe the differences between continuous and discontinuous variation, using examples of a range of characteristics found in plants, animals and microorganisms
  • explain both genetic and environmental causes of variation
  • outline the behavioural, physiological and anatomical (structural) adaptations of organisms to their environments
  • explain the consequences of the four observations made by Darwin in proposing his theory of natural selection
  • define the term speciation
  • discuss the evidence supporting the theory of evolution, with reference to fossil, DNA and molecular evidence
  • outline how variation, adaptation and selection are major components of evolution
  • discuss why the evolution of pesticide resistance in insects and drug resistance in microorganisms has implications for humans

Unit BY2
All organisms are related through their evolutionary history:
  • Biodiversity is the number of different organisms on the planet. Biodiversity varies spatially and over time
  • Biodiversity has been generated through natural selection and adaptation over millions of years. Adaptive radiation e.g. Darwin’s finches on the Galapagos
  • Organisms are classified into groups based on their evolutionary relationships. Classification places organisms into discrete and hierarchical groups with other closely related species. The need for classification and its tentative nature. Characteristic features of Kingdoms: Prokaryotae, Protoctista, Plantae, Fungi, Animalia
  • Animal biodiversity is classified into over 20 major phyla and several minor ones with each phylum containing organisms based on a basic blueprint. Basic features of: Annelids, Arthropods, Chordates. Arthropods are subdivided into four groups (details not required). Some phyla contain many more species than others
  • Physical features and biochemical methods can be used to assess the relatedness of organisms. DNA ‘genetic fingerprinting’ and enzyme studies show relatedness without the problem of morphological convergence
  • All organisms are named according to the Binomial system. The species concept
At AS, OCR seems to be the most comprehensive (although many of the exam boards make up for it at A2). AS is mostly concerned with biodiversity and natural selection - more complex ideas of speciation are to be left until A2. Some boards mention phylogenies (morphological and molecular) at this stage, but you'll find others wait to A2. I particularly like WJEC's statement for the module, that "all organisms are related through their evolutionary history".

Monday, 3 January 2011


Here are the relevant parts of the GCSE specifications for evolutionary palaeobiology. GCSE Chemistry contains some aspects of climate change, and GCSE Physics has some astrobiology and the evolution of our atmosphere, but this'd be a humongous post if I included all that.

Unit B1
Candidates should use their skills, knowledge and understanding of how science works:
  • to suggest how organisms are adapted to the conditions in which they live
  • to suggest the factors for which organisms are competing in a given habitat
  • to suggest reasons for the distribution of animals or plants in a particular habitat
  • to suggest reasons why scientists cannot be certain about how life began on Earth
  • to interpret evidence relating to evolutionary theory
  • to suggest reasons why Darwin’s theory of natural selection was only gradually accepted
  • to identify the differences between Darwin’s theory of evolution and conflicting theories [Yes, this does mean they have to look at Lamarckism...]
  • to suggest reasons for the different theories
There really isn't much more about evolution. I'm not a fan of AQA, either at GCSE or at A-Level. The GCSE course does not really deal in depth with anything (although GCSE Chemistry has a pleasing amount of geology in it), and the A-Level exams are an exercise in obfuscation (you may remember some outcry about the infamous "shrews" paper of January 2010.

Pupils should:
  • learn that living organisms are adapted to survive in the environment, for example, adaptations to life on land, and in water
  • understand how variation and selection may lead to evolution or extinction, including:
    - natural selection as variation within phenotypes and competition for resources leading to differential survival
    - the implications of natural selection for the concept of evolution as a continuing process
Of all the boards, this has the least evolutionary content. The role of the fossil record as evidence for evolution is not on the Northern Ireland Programme of Study, whereas it is for England and Wales. This is disappointing, but not surprising. The students are, however, expected to be able to identify and classify a large number of plants, animals and fungi, so with any luck they should have good taxonomical knowledge.

Unit B1
Students will be assessed on their ability to:
  • describe how organisms in an ecosystem compete with each other for resources
  • explain population data in terms of predator-prey interdependence and intra-species competition
  • demonstrate an understanding of how computer models can be used to study populations, and show an awareness of the advantages and disadvantages of these models compared with real data
  • demonstrate an understanding of the principles of natural selection, to include:
    - how individuals within a species can have characteristics that promote more successful reproduction (survival of the fittest)
    - how, over generations, the effects of natural selection result in changes within species and the formation of new species from genetic variants or mutants that are better adapted to their environment
    - how species that are less well-adapted to a changing environment can become extinct
  • explain how fossils provide evidence for evolution
  • discuss why Charles Darwin experienced difficulty in getting his theory of evolution through natural selection accepted by the scientific community in the 19th century
  • explain the principles of classifying organisms and the difficulties encountered in attempting to do so, as illustrated by the five kingdoms, the use of phylum, class, order, family, genus, species and the main characteristics of the five vertebrate groups
Unit B2
Students will be assessed on their ability to:
  • explore the principles of interdependence, adaptation, competition and predation and explain how these factors influence the distribution and population sizes of organisms in a given terrestrial or aquatic environment
  • interpret data on environmental change
  • describe the special nature of some extreme environments, notably deep sea volcanic vents, the Antarctic and high altitudes
Unit B3
At the end of this unit students will be able to describe and explain the following statements and carry out the tasks indicated:
  • vertebrate herbivores may feed in large groups or herds, and they may do so for protection in numbers. This is a successful evolutionary strategy, even though some members of the herd may be killed
  • some animals, in particular birds and mammals, have developed special behaviours for the rearing of young, since they display parental care
  • parental care is a successful evolutionary strategy; although it involves risk to the parents, it can increase the chances of survival of the parental genes
I like the final section that deals with behaviour and ethology, but it does rather skirt over evolution - it's something that can be covered in a double period if the teacher feels like it.

Module B3
  • recall that the many different species of living things on Earth (and many species that are now extinct) evolved from very simple living things
  • recall that life on Earth began about 3500 million years ago
  • understand that evidence for evolution is provided by fossils and from analysis of similarities and differences in DNA of organisms
  • recall that the first living things developed from molecules that could copy
  • understand that these molecules were produced by the conditions on Earth at that time, or may have come from elsewhere
  • recall that evolution happens due to natural selection
  • understand the process of natural selection in terms of variation, competition, increased chance of survival and reproduction, and increased number of individuals displaying certain characteristics in later generations
  • understand that variation is caused by both environment and genes, but only genetic variation can be passed on
  • explain the difference between natural selection and selective breeding
  • interpret data on changes in a species in terms of natural selection
  • recall that changes can occur in genes (mutations)
  • understand that mutated genes in sex cells can be passed on to offspring and may occasionally produce new characteristics
  • understand that the combined effect of mutations, environmental changes and natural selection can produce new species
  • understand that if the conditions on Earth had, at any stage, been different from what they actually were, evolution by natural selection could have produced different results
  • when provided with information about alternative views on the origin of life on Earth, or the evolutionary process:
    - can identify statements which are data and statements which are (all or part of) an explanation
    - can recognise data or observations that are accounted for by, (or conflict with), an explanation
    - can identify imagination and creativity in the development of an explanation
    - can justify accepting or rejecting a proposed explanation on the grounds that it accounts for observations; and/or provides an explanation that links things previously thought to be unrelated;
    -can identify a scientific question for which there is not yet an agreed answer and suggest a reason why
    - can suggest plausible reasons why scientists involved in a scientific event or issue disagree(d)
    - can suggest reasons for scientists’ reluctance to give up an accepted explanation when new data appear to conflict with it
  • recall that the evolution of a larger brain gave some early humans a better chance of survival
  • understand human evolution in terms of a common ancestor, divergence of hominid species, extinction of all but one of these species
  • when provided with additional information about human evolution, can draw valid conclusions about the implications of given data for a given theory, for example:
    - recognises that an observation that agrees with a prediction (derived from an explanation) increases confidence in the explanation but does not prove it is correct
    - recognises that an observation that disagrees with a prediction (derived from an explanation) indicates that either the observation or the prediction is wrong, and that this may decrease our confidence in the explanation
  • understand that a rapid change in the environment may cause a species to become extinct, for example, if:
    - the environmental conditions change
    - a new species that is a competitor, predator or disease organism of that species is introduced
    - another organism in its food web becomes extinct
    - understand that species have become extinct (or are in danger of becoming extinct) and that this is likely to be due to human activity;
  • recall two examples of modern extinctions caused by direct human activity, and two caused by indirect human activity
The real issue I have with OCR is that they are still pussyfooting around the issue that evolution may not be true. I'd like to see the chemists having to hedge their teaching about collision theory on the grounds that, while there is a lot of evidence, this does not prove that collision theory is true and that there may be an alternative explanation that allows people to continue worshipping their invisible sky fairy without questioning their belief that Homo sapiens is different in some way...

Biology 1
Candidates should:
  • know that organisms that have similar features and characteristics can be classified together in a logical way. Understand the need for a scientific system for identification and scientific as opposed to 'common' names.
  • use local first and/or second hand data/ICT simulation to compare the variety of organisms which live in particular habitats, and investigate how the organisms in an area are affected by other organisms
  • explore information about the morphological adaptations shown by organisms which enable them to survive in their environment
  • understand that new genes result from changes, mutations, in existing genes and that mutations occur naturally at random. Mutations may be beneficial or harmful and are increased by exposure to radiation and some toxic chemicals
  • variation is the basis of evolution
  • examine evidence and interpret data about how organisms and species have changed over time. Suggest reasons why species may become extinct
  • consider how individuals with characteristics adapted to their environment are more likely to survive and breed successfully. Consider the uses and limitations of modelling to illustrate the effect of camouflage colouring in prey and predator relationships
  • know that the genes which have enabled these better adapted individuals to survive are then passed on to the next generation. This is natural selection
  • consider the process of data collection, creative interpretation and deduction that lead Charles Darwin to propose the theory of evolution. Discuss the controversy surrounding the acceptance of the theory. Discuss evidence that evolution is ongoing such as data on Warfarin resistance in rats
This isn't too bad, but Edexcel and OCR still show more evolution discussion. So some examination boards are rather detailed when discussing evolution, extinction and adaptations. Speciation is, however, skirted around at best and actively ignored at worst. It's worth remembering when pitching outreach to these students, that only the CCEA require their students to know the major phyla and groups within the vertebrates, and I doubt even my current A2 students would know what a bryophyte was if I smacked them about the head with one. New species are not going to be very exciting for this age group (unless it's a big toothy dinosaur), but any discovery that demonstrates adaptation, new observations of behaviour, or perhaps transitional forms/two new gaps in the fossil record, might be worth pitching to a GCSE group.

Sunday, 2 January 2011

Making Your Research Suitable For Outreach

Last Tuesday I was able to catch up with good friend Dave Hone of the Archosaur Musings blog. He mentioned that grant application forms are more frequently asking (nay, demanding?) applicants to demonstrate how they will engage in outreach relating to the specific research project for which they are applying for funding, something he later posted about on his blog.

Dave said it was no simple task, given the complexity and perhaps obscurity of [insert name of Dave's project here]. Nonsense! said I. And I grabbed a copy of the A2 Biology textbook for my exam board and shoved the pages about evolution, speciation and adaptation in his face. What came out of that discussion was that a) very few researchers have a scoobies what criteria are examined in high school qualifications, b) knowing this would certainly make grant applications a little easier, and c) it would be awesome if a fantastic, selfless and damn sexy lecturer-blogger could put together the details. They weren't available, so I said I'd do it.

Of course, this will be of absolutely zero interest to any researchers outside of the UK, and for now this will be simply those assessment criteria relevant to evolution, ecology and palaeontology. If there are sufficient requests from readers for other fields (e.g. biochemistry, physiology, inverts etc) then make them known.

There are three English examining boards: Edexcel, OCR and AQA. Additionally, there is one Welsh board, WJEC/CBAC and a Northern Irish board, CCEA. All five of these offer GCSEs, sat at age 16, and A-Levels, sat at age 18. There are other qualifications, such as baccalaureates and BTECs, but they are not as common, nor, have I found, is there as much opportunity for the discussion of evolution and palaeontology. There is also a Scottish examining board, SQA, of which the most common qualifications are Standard Grades and Highers. I'll try to tackle SQA as well, with the caveat that I am not as familiar with these examinations as I am with GCSE and A-Level.

Rather than looking at each board individually, I intend to divide as follows:
When I've finished each, I'll update the links.
Related Posts Plugin for WordPress, Blogger...