Human evolution and how science works

I am just finishing up a fairly in-depth look at the theory of evolution with my Grade 12 students. Towards the end we study human evolution, which offers a great opportunity to illustrate how science changes as our knowledge develops and new facts become available. Each year, before I teach this topic, I have a quick scan of a website such as Science Daily to see what the latest findings are in the field of paleoanthropology. 

Two recent publications highlight the rapidly-changing nature of our current thinking in relation to human evolution.

Image via Pixabay

The first article, published in the journal Nature and summarised here, puts back the arrival of hominins in east Asia several hundred thousand years, from 1.8 million to 2.1 million years ago. Hominins are the evolutionary line that led to us, Homo sapiens, as well as earlier Homo species and members of the genus Australopithecus. The article clearly illustrates to students how, as new evidence becomes available, our scientific knowledge can be updated accordingly. 


The second article, published here in the open access journal Trends in Ecology & Evolution, claims that recent evidence no longer supports the notion that H. sapiens evolved in a localised area in east Africa, and instead shows a more complex, geographically-dispersed evolutionary history throughout Africa. The authors conclude that this changing view, of a more 'mosaic-like' evolution of recent human ancestors in a multi-regional pattern across Africa, means that earlier hypotheses and assumptions need to be adjusted to take these new facts into account. The article also highlights knowledge gaps and areas in which future research should focus. This can be used to reinforce with students the point that good science often asks as many new questions as it answers existing ones. 

By using examples like this from the field of paleoanthropology, students get to see both the latest research and the ever-changing nature of science. 

Three reasons behind common misconceptions in biology

Recently I saw a link to an interesting news article about biology students' misconceptions of the subject. When I read the article I noticed that many of the misconceptions identified chimed with observations I have made of my own students' misconceptions. Intrigued, I downloaded the original research article on which the news item was based, which can be found here. The authors identify three common underlying causes, or cognitive construals, for these misconceptions, each of which I will look at in turn.

Rafflesia, a parasitic plant (Photo credit: Dick Culbert)

1. Teleological thinking

The first common underlying cause of misconceptions, teleological thinking, refers to our need for causal stories behind the observation of phenomena, based on the assumption of goals, purposes, or functions. An example of this underlies one of the most common misconceptions I come across from students when teaching evolution. Here is a sentence I might commonly see from a student who is explaining the evolution of the body form of dolphins:

'The ancestor of dolphins walked on land but lived near water. Eventually dolphins adapted themselves so they could swim in the water'. 

Here, the student is assuming a purposeful effort from a dolphin ancestor to change itself into a form more suited to a life aquatic. Clearly this represents a fundamental misconception of natural variation, natural selection, and changes in the makeup of a population over time. Individual organisms cannot 'adapt themselves' to their environment. Natural variation in a population means that some individuals may be better suited to their environment and are therefore more likely to survive and reproduce. The traits that make them more fit for their environment therefore become more prevalent in the population. 

This is a tricky concept for native speakers to express correctly, and would seem to be linked to the underlying teleological misconception that evolution is a purposeful process. For my students, who are ELLs, they have to cope with both the difficulty of the concept and the use of language to correctly express it. Knowing the nature of this misconception, however, will enable me to help learners address these issues when they encounter them in the future. 

2. Essentialist thinking

The second type of misconceptions are related to essentialist thinking - a set of assumptions an individual may make about concepts, such as the idea that a particular feature of a system is solely responsible for defining its overall identity. In biology, an example of this would be the misconception that all plants are photosynthetic. Rafflesia, the plant which produces the largest flower in the world, is parasitic and does not make carbohydrates through photosynthesis. In fact, in biology there is frequently an exception to every 'rule'. Thus we need to help move students' understanding away from the idea that systems or processes need not be defined by a particular characteristic most of them share. 

3. Anthropocentric thinking

The third misconception occurs when biological phenomena are viewed through an anthropocentric, or human-centred lens. A common anthropocentric misconception which I have been battling for a long time now, and remember being used as an example of science undergraduates' misconceptions during my MAEd, is that plants take in food from soil via their roots. This misconception can be addressed simply by asking students if this were the case, why then are there not enormous holes in the ground at the base of every tree on the school grounds? However, knowing that the underlying, anthropocentric reason for this misconception - that all organisms, including plants, must 'eat' food in a similar way to humans - is helpful, and provides a means for approaching similar anthropocentric misconceptions. 

Summary

The insights afforded by understanding the underlying causes of common misconceptions among biology students are both interesting and helpful. Interesting, in that these misconceptions would appear to be widespread, irrespective of culture or language (although there may of course be some communities where they may not be present. Helpful, in that by understanding the underlying causes of these misconceptions, it can provide biology teachers with a means with which to address them. In turn, once learners become more aware of these causes, they too may be able to spot them more easily and avoid falling into these common traps. 

I would love to hear others' experiences of common misconceptions and ways of dealing with them. 

Using citizen science to support global learning connections

Last week's #AsiaEd slow chat on Twitter discussed how we as educators can help our learners become globally connected citizens. As a follow-up I will outline what I think is a great way to do this, which is by encouraging students to get involved in citizen science. I have written previously about how I have introduced my students to citizen science, which is essentially science carried out by amateur, non-professional scientists. In this post I will outline various citizen science projects and websites which offer opportunities for students to participate in citizen science. I will also explain why I think these kinds of projects are useful for helping learners to become globally connected citizens. 

Dr Lin Chambers from NASA has a videoconference with students who participated in the S'COOL project.

NASA


NASA has a number of citizen science projects, for example the CloudSat and S'COOL projects. Students participate in these activities by making careful observations of the sky conditions - cloud cover, cloud types etc - then uploading these data to the respective project web sites. One of the aims of these projects is to reconcile surface observation data with observations made by sensors on satellites, in order to try and improve the accuracy of the sensors. By taking part in these projects students can make connections on a global scale. This includes making connections with the science, for example the global nature of climate science. It also includes making connections with a global community of both citizen scientists (other schools who are engaged with these projects) and professional scientists, for example NASA climate change specialists. Students at my school have participated in videoconferences with NASA scientists and with a school in the US which also participates in the S'COOL project.

A student presents some data for the NASA S'COOL project videoconference.

SciStarter

SciStarter is a very useful website which contains links to a large range of different projects in which volunteers can get involved. Their website has a search function that allows you to select and search for a variety of topics and activities. There are links to many different projects across a range of fields. 

Zooniverse

Another great website which has a variety of citizen science projects across a range of disciplines is Zooniverse. Projects include Snapshot Serengeti, where volunteers help to classify animals in photos taken by camera traps, and Asteroid Zoo, where work is conducted to identify near Earth asteroids. 

Journey North

Journey North is a website dedicated to monitoring wildlife migrations and seasonal change. It also has a number of resources for educators, such as activities, slide shows and teacher guides. 

Project Noah

Project Noah is an online tool for documenting biodiversity around the world. Anyone can join, and once signed up members can upload photos of wildlife they have taken, along with details of the organisms they spotted. This information can then be used by ecologists in various ways, for example to track the spread of invasive species, or to determine if climate change is having an impact on the geographic range of a species. 

Summary

Citizen science affords students the chance to make global connections between what they are learning in the classroom, and the community of practice of scientists. It also provides them opportunities to become globally connected with other learners around the world. There are many different citizen science projects with which learners can sign up to and get involved. By encouraging our students to engage in these kinds of activities we can provide fantastic opportunities both for learning about real science in an authentic fashion, as well as affording rich experiences for learners in a globally connected environment. 

High school lab classes - are they obsolete?

Are high school lab classes still relevant or necessary any more? Or are they an obsolete approach from a bygone era?

Many have argued that science practical classes are formulaic and lack challenge and interest for learners. The argument is that such classes should give opportunities for students to undertake experimental design, and analyse and interpret data - in short, to practice science as it is practiced in the real world.

In principle these are good ideas - blurring the distinction between the classroom and the real-world by moving deeper into the ways a community of practice actually operates. The problem is, as so often, one of time. How can learners be expected to design an experiment, for example, if they have yet to have hands-on experience of basic lab techniques? How can they identify potential areas of error if they simply have not encountered these situations before?

I would argue that there is a place for both relatively structured practical classes, and for open-ended, investigative classes - they do not have to be mutually exclusive, or have one approach ditched in favour of the other. 

In practice, the emphasis of a lab class would vary depending on which skills are being highlighted. For example, an experiment investigating the effect of temperature on enzyme activity is relatively simple to design, and learners could be expected to do a reasonable job of it. However, I see it more as an opportunity to practice a wider range of skills, including not just taking and recording measurements, but also data analysis, interpretation, and error identification. Groups could compare their own results with the rest of the class, and gain an appreciation of the importance of pooling larger datasets for greater accuracy. These are exactly the skills advocated by those who suggest lab classes are formulaic. Once these basic skills are in place, then learners would be ready to take on a more in-depth, open-ended inquiry of their own. 

We cannot expect learners to come as ready-formed junior scientists in the making. It is still the role of science teachers to guide learners, whilst providing opportunities for more exploration and open-ended investigation once they have mastered the basics. 

I'd love to hear others' opinions on this...

Using Google Classroom for the first time

The new school year has just started here in Thailand, and one of the changes I am planning this year is to use Google Classroom. I have used various Google Apps in class previously, and found them to be very useful, particularly as collaborative tools. However, this will be the first time I have used Google Classroom itself. 

I will be piloting the use of Classroom with my Grade 10 students as part of their basic biology course. A key thing when integrating new technology is not to take on too much too soon, so I'm not rolling it out for my other courses as yet. For now I will also continue to use Moodle as an LMS for posting resources such as videos, links to useful websites and so on, but any productive work such as written assignments will be done via Classroom.

The school band playing as school opens for the year.

Pedagogical rationale

As with any EdTech integration it is important to think about pedagogy first and then see what technology may be suitable in achieving the pedagogical aims. 

In this case the rationale behind using Google Classroom includes the following:

• To facilitate more collaborative learning
• To make learning more visible, by allowing rapid feedback to learners, from both me and, just as importantly, from their peers
• To clarify and consolidate links between topic areas within ecology
• Following on from the previous point, to enable stronger links to be made between the classroom and the real world, by demonstrating more clearly how the different sub-topics relate to the overarching theme of the interdependence of living things with each other and their environment
• To form the basis of a digital portfolio

I foresee a couple of potential hurdles with this approach. There may be technical issues, such as how to deal with group work assignments, although there are a few workarounds for this. Classroom is still a work in progress, so there may be other, unforeseen technical challenges. Also, there is a danger of 'Google fatique', if learners become tired of using the same platform repeatedly. Hopefully, however, this project will proceed smoothly and according to plan. Alternatively I may be pulling my hair out and spending a lot of time lurking on the Google+ Classroom community page!

Creating virtual field trips

 Field trips are a fantastic way to engage students and enhance learning. Sometimes, however, field trips may not be possible for a variety of reasons, for example financial, geographical, or safety reasons. In these cases a great substitute is a virtual field trip. This is an interesting way to introduce learners to different out-of-classroom environments. 

Virtual field trips can bring learners face to face with wild animals!

A very useful tool for creating virtual field trips is Google Tour Builder. (Note that the 32 bit Tour Builder app will not run on 64 bit browsers, such as Chrome, so you may need to open it in Firefox or Safari).

An example is an aquatic ecosystems virtual field trip that I use as part of my ecology course with grade 10 biology students. The virtual field trip is used to introduce the topic, and includes questions for learners as they progress through the trip. Once they have completed this task, I ask them to work in pairs or small groups to create a virtual field trip of their own based on an aquatic ecosystem of their choosing. 

Learners can experience new or unusual environments.

Where possible I like to use my own photos, which provides an additional talking point for students. Alternatively, a useful place to get photos online is photosforclass.com, where you can search for photos that have been uploaded to Flickr and have been licensed by their owners to be sued for educational purposes. 

Clearly, there are many possible applications for virtual field trips: a trip to a museum, a gallery, a zoo, different terrestrial ecosystems, and so on. If a real field trip isn't an option, a virtual field trip may be the next best thing.

Encouraging learner voice and choice

Offering learners more voice and choice is increasingly being advocated as a way to improve engagement and personalise learning. Edna Sackson, from Inquire Within, also mentioned this to me following an earlier post. One of the ways in which I have attempted to achieve this is to give learners the choice of what finished product to submit at the end of the assignment. As ever with this particular assignment, student groups could choose any topic within the broader scope of genetic engineering (e.g. GMOs, cloning, forensic biology etc). However, instead of specifying a finished product that involved a report, or a PowerPoint presentation to the class, I gave them the option of what kind of final product to submit.

Upon completion of the assignment final products submitted included infographics produced in easel.ly, presentation-style reports in Prezi, and PDFs created via Google Slides. Many of the students were unfamiliar with some of these applications, and so were finding their feet with them to some extent. One interesting observation was a student who was explaining to her group members how to find their way around Adobe Illustrator. This was a good example of the teacher stepping back and ceding peer teaching opportunities to the students – I’ve never used Adobe Illustrator in my life! Other spontaneous peer teaching included students showing each other tips and tricks in Photoshop.

Student feedback following an evaluation at the end of the assignment was generally positive, with some neutral responses. Encouragingly, there were no negative responses, although Thai students are often reluctant to criticize even via anonymous evaluation forms!  

Reasons learners gave for enjoying the assignment included the freedom it offered them, that it was fun, it enabled them to use their creativity, and it offered them the chance to learn new skills, such as how to use Prezi or make infographics.

I also asked learners what aspects they would change or improve. Suggestions ranged from having groups present their work to the rest of the class (even if the final product was not a traditional presentation format) to requesting that I assign (!) topics to groups because some groups were deemed to have chosen “easy” topics. Obviously, this latter suggestion would somewhat defeat the purpose of this exercise.

I’ll finish up with a couple of direct quotes from the students regarding this assignment. The first quote supports the idea that learners appreciate the chance to be creative, the second one – well, what can I say!

“I really love this project because we have to use lots of skills not only understanding and writing but we also have to be creative to make an easy-reading infographic”.

“Its kind of fun using technology with the subject which seems to be boring like biology”.

Using the SAMR model to conceptualise asynchronous discussion forums

Asynchronous discussion forums (ADFs) are text-based, online forums that individuals can access at a time and place of their choosing. In this post I will discuss how ADFs can be conceptualised for learning at all levels of the SAMR model developed by Dr Reuben Puentedura. The SAMR model offers a way to consider the different levels at which technology may be integrated into teaching and learning: Substitution, Augmentation, Modification, or Redefinition.

Substitution
The obvious case to make here is that ADFs can facilitate an online debate that acts as a substitute for a more traditional classroom debate. There are similarities between the two approaches in that the debate would generally involve a topic that generates a certain amount of controversy, for example embryonic stem cell research, and learners would be expected to employ critical thinking skills and evidence-based arguments. The key differences are that in an ADF-mediated debate, learners would be practicing written rather than oral language skills, and they would have more time to gather evidence and make their case. 

Augmentation
Although ADFs could be substituted for a classroom debate, they need not replace it entirely. They could be used as a pre-debate activity, providing learners with an opportunity to gather evidence and refine their arguments. Alternatively, the classroom debate could be used as a lead-in activity to generate interest for the subsequent online debate. In either case, the ADF augments the classroom debate by affording learners a space in which to engage in dialogue over a longer time frame. 

Modification
This brings us to the modification aspect of ADFs, where learners can engage in a debate for longer, and potentially more deeply, as well as providing direct links to evidence that supports their case. They and their peers have more opportunity to evaluate these evidence bases, and thus they are moving away from what is offered by a traditional classroom debate. 

Redefinition
ADFs can redefine the traditional classroom debate by extending learner agency, for example by providing opportunities for knowledge creation as opposed to knowledge acquisition (McCormick and Scrimshaw, 2008). By posting to an ADF students are able to synthesise what they have learned, express it in their own words, and negotiate meaning with their peers. ADFs thus enable learners to engage “in the dialogues through which knowledge is constantly being constructed, deconstructed and reconstructed” (Wegerif, 2006a). This would not be possible in quite the same way during a classroom debate because of the more fleeting nature of verbal interactions.

An additional agentive feature of ADFs is that they look both forwards and backwards, pedagogically speaking (Lankshear and Knobel, 2008). That is to say, they provide learners with an opportunity to explore new understanding, whilst also demonstrating existing knowledge and skills. Consequently, there are more opportunities for students to learn from their peers, rather than from their teacher.

A further important affordance of ADFs is the increased opportunity for learners to engage in higher-level thinking. When I analysed the forum statistics following an ADF debate I assigned to my Grade 10 students, the number of views far exceeded the number of posts, supporting the notion that many students were reading the existing discussion before posting, i.e. engaging in higher-level thinking before participating, rather than simply posting for the sake of it. This is consistent with Saade and Huang’s (2009) findings from their university-based study of learners using an ADF, and is arguably an advantage ADFs have over traditional classroom debates, where learners don’t necessarily have the time for higher-level thinking before making a contribution. ADFs also clearly demonstrate how technology can facilitate social learning, i.e. computer-supported collaborative learning (CSCL) (Stahl et al., 2006; Wegerif, 2006b).  They are computer-mediated communication environments that “turn communication into substance” (Dillenbourg, 2005, in Stahl et al, 2006, p.12). Or, put another way, ADFs reify learners’ participation in a discussion, leading to the negotiation of meaning (Wenger, 2008). 

ADFs can record learner activity as well as being a product of their thinking. These records of interaction and collaboration have been identified as potentially important resources for improving intersubjective learning (Stahl et al, 2006). Intersubjective learning considers that individual meaning making comes about through social interactions with others, and is partly constituted by those interactions (Suthers, 2006). It could be argued that traditional classroom debates afford this as well, but again the asynchronous nature of ADFs allows more time over which these interactions may occur. 

A final point about ADFs is that they provide a great opportunity for metacognition, or making learners’ thinking more visible. For example, the forum software I use has a peer-grading facility. As learners grade the contributions from their peers, it helps them to focus on what they could do to improve their own contributions, and thus they are thinking about how to improve their own learning. I feel that ADFs can be conceptualised at each level of the SAMR criteria, including the key levels of modification and redefinition, for the reasons outlined above. In a future post I will return to ADFs and discuss how they may be used to enhance both general and subject literacy.

References

Lankshear, C. and Knobel, M. (2008). New ways of knowing: Learning at the margins, in Hall, K., Murphy, P., and Soler, J. (eds.). Pedagogy and Practice, London, Sage in association with The Open University

McCormick, R. and Scrimshaw, P. (2008). Information and communications technology, knowledge and pedagogy, in Murphy, P. and McCormick, R. (eds.). Knowledge and Practice, London, Sage in association with The Open University

Saade, R.G. and Huang, Q. (2009). Meaningful learning in discussion forums: Towards discourse analysis. Issues in Informing Science and Information Technology, 6, pp.87-99

Stahl, G., Koschmann, T., and Suthers, D. (2006). Computer-supported collaborative learning: An historical perspective. In R. K. Sawyer (Ed.), Cambridge handbook of the learning sciences (pp.409-426). Cambridge, UK: Cambridge University Press. Available at http://GerryStahl.net/cscl/CSCL_English.pdf last accessed 01/02/2015

Suthers, D.D. (2006). Technology affordances for intersubjective meaning making: A research agenda for CSCL. International Journal of Computer-Supported Collaborative Learning, 1, 3. Available at http://lilt.ics.hawaii.edu/papers/2006/Suthers-ijCSCL-2006.pdf; last accessed 01/02/2015

Wegerif, R. (2006a). Dialogic education: what is it and why do we need it? Education Review, 19, 2, pp.58-66

Wegerif, R. (2006b). A dialogic understanding of the relationship between CSCL and teaching thinking skills. Computer-Supported Collaborative Learning, 1, pp.143-157

Wenger, E. (2008). Meaning, in Murphy, P. and Hall, K. (eds.). Learning and Practice, London, Sage in association with The Open University

Towards a more active classroom

Before becoming a teacher I worked in public health in the UK. One of my roles was to help disseminate data, involving seminars, workshops etc. I remember a specific occasion when I was involved with a one day workshop, delivering various public health data to a range of professionals in the field. When I came to analyse the feedback questionnaires after the event I was struck by the wide variation of responses. For example, one delegate noted that they were happy the event had been held over a full day, but would have preferred it to be held over two days so there was more time for discussion. On the other hand, a different delegate declared that they felt a full day was excessive and the proceedings could have been dispensed with in a morning. What I took from these responses was that the timing of the event was probably about right!

Similarly, when I analyse my anonymous course feedback questionnaires that I have students complete at the end of my biology course, if I see a range of responses like this I feel that I am probably getting that particular aspect of my classes about right. However, what has become clear from administering these course evaluations is that my students felt that some of my classes did not result in a suitably active classroom. Therefore this is an area that I am currently focusing on in my lesson planning. 

I'm aiming for a more active classroom with all of my classes, for example I have increased the number of lessons where students are engaged in peer-teaching. The photos below show Grade 10 students preparing for and delivering a peer-teaching activity relating to protein synthesis. 

I am also re-designing a section of my course relating to nervous systems. I have all the materials I need from previous years, but I am going to take a different approach with them in the classroom. Some classes will be problem-based, while other work will provide learners with an opportunity to develop a final output of their own choosing, e.g. an infographic, a poster, or an animation. This is also an excellent opportunity to make students' learning more visible, by including a section looking at how the human brain learns, together with recent developments in neuroscience and the way we understand learning, and encouraging students to reflect on how this relates to their own experiences as learners.

I will know in a few weeks time whether or not my attempts to make a more active classroom have been successful…