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. 

Hiking in an Ecuadorian cloud forest

A new experience for me recently was to go hiking in a cloud forest, in Maquipacuna Forest Reserve, Ecuador. Located just a couple of hours drive from the capital, Quito, this is a great place to explore the natural beauty of mainland Ecuador. 

On the drive to Maquipacuna from Quito it is possible to visit the 'middle of the world' monument - latitude 00° 00' 00''. You can also stop at Pululahua, an extinct volcano whose crater is now farmed to take advantage of the fertile volcanic soil.

Heavy rainfall meant that we had to negotiate landslides on the way to the cloud forest - there was a 30 minute wait while the road was cleared for the one shown below. 
























Set up by an Ecuadorian couple, Rebeca and Rodrigo, in order to conserve the cloud forest, the non-profit Fundacion Maquipucuna now employs several local people, and the reserve covers an area of 6000 hectares. Large swathes of secondary forest are growing back in reclaimed land around the central area of primary forest. The ecolodge itself sits in the middle of the forest and is surrounded by hummingbirds and other forest wildlife. 

The weather was very different to the previous week we spent in the Galapagos Islands!

Although when we visited it was not the right season to see the famous Spectacled Bears, there was plenty of other wildlife to be seen, especially birds and insects. A variety of hiking trails were available, many of which were clearly marked and did not require a guide. Others were more challenging and a guide was recommended, and guides were also helpful for spotting and identifying wildlife. Local guide Arsenio had an encyclopaedic knowledge of the local birdlife, and took us on an early morning hike when we spotted a toucan, hawks, toucan barbets, and many more. 

We spotted this basilisk on the river bank early one morning.

There was also an in-house entomologist staying at the ecolodge, Nancy Miorelli, who provided guided night walks. There was an incredible variety of insect life in the forest, with just a few examples shown below. 

More heavy rainfall prior to leaving for the return journey to Quito gave us cause for concern, but thanks to our driver Bernardo we made it back safely! 

10 great websites for HD science videos

When my school recently installed new HD interactive touch screens, I realised that I was going to have to change a few things. David Attenborough has produced some amazing natural history programmes. However, a poor quality, pixelated clip of him, along with some flowers blooming in the desert following a brief period of rain, uploaded by the BBC to YouTube several years ago, was no longer going to cut it on these HD screens! 

Via Pixabay

I therefore decided to go through my bookmarked websites to consolidate those with high quality biology videos and animations, as well as look for new sites with good quality, HD content. It was also important to me that these sites were uploading their content specifically for educational purposes. I don't want illegally uploaded clips that may be taken down at any point by their copyright owner. Although fair use of copyright material generally allows use for educational purposes, I feel it is better to avoid potential issues by using material where permission has been explicitly given. This also helps to model good digital citizenship for students. 

So, in no particular order, here is a curated list of excellent video or animation resources, along with a brief description of what each site offers. They are mostly life sciences-oriented, although some are more general science websites. 

Your Genome 

Excellent, high quality animations covering various molecular biology topics, including DNA replication, protein synthesis, and the molecular basis for cancer. It also has short videos with interviews with practising scientists, plus some great hands-on activities.

HHMI BioInteractive

A multitude of resources on a wide range of life science topics. I have found the ecology videos and activities relating to Gorongosa National Park, in Mozambique, particularly helpful and engaging. There are also very useful evolution and natural selection resources, for example the activities based on real data from rock pocket mouse populations and their adaptations.  

Big Picture 

This site also has a variety of life science resources, including videos, animations, and activities. The videos and animations are of a very high quality, for example this animation about the sliding filament theory of muscle contraction. There is a particular focus on making links between cutting-edge science and the wider implications for society as a whole. 

Stated Clearly

A website with high quality animations by Jon Perry, focused mainly on giving clear explanations on various aspects of evolutionary theory, natural selection, and genetics, for example this one about how cooperation between species evolved. My students also really enjoyed the animated RNA molecules in this video about the RNA World Hypothesis! 

Deep Look

Punchy, extremely high quality HD videos on various different biology topics. I particularly like the mosquito biting video, which I have used to introduce the topic of mosquito-borne disease. The hummingbird's flight in slow motion is very useful for engaging students on the topic of animal movement, while this video looks at squirrel behaviour. 

Amoeba Sisters

Lots of fun, high quality animations covering all of the key biology topics. These videos would be great for flipped classrooms. They could also be used to introduce topics, or for review at the end of a topic. 

It's Okay To Be Smart

A wide range of science videos, including biology, grouped by subject. For my students, who are all Thai and therefore English language learners, the speed at which the presenter speaks could pose a challenge - fortunately, the videos have closed caption subtitles which can be switched on if necessary. 

StemBox

This YouTube channel has videos based around practical STEM activities aimed specifically at making STEM more accessible to girls aged 7-13 years. There are lots of good ideas here that could be used for introductory science labs for younger kids, or at summer camps etc. 

Draw Curiosity

This YouTube channel by Ines Laura Dawson features an eclectic mix of videos on a range of science topics, such as why two sexes evolved, and how to build a cyborg beetle. Ines also has a Draw Curiosity website with more videos and blog posts.  

Frank Gregorio

A range of videos set to uplifting, awe-inspiring music by Frank Gregorio. I use the Introduction to Biology video as an attention grabber when I see my new class of Grade 10 students for the first time at the start of our three years studying biology together, and it always prompts a round of applause! 

Bonus tip! Don't want YouTube comments below a video you want your students to watch? Use ViewPure to remove comments and other distractions from YouTube videos!

I hope this list of websites is useful. It would be great to hear suggestions about other, similar websites that I've not included!

A visit to the Galapagos Islands

A long-held ambition was recently fulfilled when Lisa and myself visited the Galapagos Islands. As a biologist, it was incredibly exciting to visit the place which had played such a key inspiration for Darwin's theory of evolution by natural selection. For their size, the Galapagos have more endemic species than anywhere else on earth. 

I am fortunate enough to have been to many places to view nature and wildlife, but few as pristine as these islands, with animals so unafraid of humans. Even in the main harbour in Puerto Ayora, on the island of Santa Cruz, the water was so clear and unpolluted there were juvenile sharks swimming between the moored boats and sea turtles popping up for air. 

Each day brought a new treat. On the first day there were the famous giant tortoises, the next day we were diving with sea lions, as seen in this video! 

A particular favourite were the marine iguanas, basking at every available opportunity. 

For bird spotters, there were the famous Darwin finches, blue-footed boobies, and even flamingoes. Frigate birds and pelicans were often to be seen at the local open-air fish market, along with a few inquisitive sea lions. 

The sea lions generally got the first pick of the sun loungers too!

Lava lizards are the most abundant reptiles on the islands.

The underwater wildlife was as spectacular as that on land - there were eagle rays and hammerhead sharks off in the blue, plus, as this video shows, reef sharks and turtles in abundance. 

The diving was challenging, with strong currents and abrupt thermoclines, but it was well worth it! (Thanks to our dive master who borrowed my camera to get this shot of a shark, below). 

The final night at our favourite place for sun-downers and wildlife spotting. This was an unforgettable trip, and the Galapagos Islands certainly lived up to their reputation as a unique wildlife experience!

Setting up a high school Climate Club

I have been helping students participate in a number of climate and weather-related activities for a few years now. These activities have included making regular cloud observations and uploading data to citizen science websites such as NASA's CloudSat project. 

Earlier this year myself and a colleague decided to consolidate the various activities we carry out into a Climate Club. This is a voluntary club for those students who are interested in learning more about the weather and climate science. It also aims to raise awareness around issues to do with climate change. This has particular relevance for my Thai students, since Thailand is identified as one of the top ten countries in the Long-Term Climate Risk Index.

Some of our Climate Club students enjoying a working lunch.

We currently have over twenty students who attend regularly, representing five out of six grade levels at my school. The club holds regular 'working lunches', where Climate Club members get to spend their lunch hour eating take-away instead of school dinners, and having fun, informal conversations around various climate-related topics. 

One of the regular items that has proved popular with students is a look at climate science-inspired art. This has included the Polarseeds project, where climate data has been used to create soundscapes, and Nathalie Miebach's art, where she creates sculptures based on weather data. This hopefully makes the club more accessible to students who may be less science-focused - moving from STEM to STEAM!

Students from the club regularly give presentations on topical climate-related issues for various events. For example, we recently held a videoconference with a scientist from NASA, where students presented on the likelihood of Thailand experiencing a La Nina event this year, as well as the implications for southeast Asia arising from the USA's withdrawal from the Paris Agreement. 

One of the key aims for the club from my perspective has been to make it as student-led as possible. To this end we have created a number of student roles and responsibilities - president, project coordinator, data analysis coordinator etc. There are also teams within the club who will take the lead on different aspects, such as a data analysis team, to explore our school's weather station data, a graphic design team, who create posters, logos etc for the club, and a website design team, who will take the lead on the Club's website. Another aspect I was keen on was that students should get some kind of recognition for the time and effort they put into the club. Thus, the website will ultimately also provide a means for members to demonstrate the work they have engaged in with the Club when they apply to university. In addition, small groups of club members take on responsibility for organising the working lunches - setting the agenda, finding climate science art to share, and suggesting new avenues for the club to explore. 

Running the Climate Club has been proving to be a fun and rewarding experience, with lots of enthusiastic and positive feedback from our student members. It is my hope that by learning about climate science in a fun and relaxed atmosphere, these students will gain a deeper understanding of the challenges posed by climate change, but also some of the ways in which we can all do our bit to mitigate its worst effects.