Biopedia

Vince's Podcasts

Biology is a fascinating subject which is well worth exploring. Its scope stretches from individual DNA strands and viruses to blue whales, metapopulations and the biosphere. We will shine the spotlight on a different biological concept in every episode. Topics I've covered in the past include the origins of cell theory, Dollo's law and the Anthropocene; however, there is still plenty more to discover. Our focus will range from the very smallest scales to the very largest; from virions to the Gaia hypothesis. So come and explore the fascinating world of biology, one episode at a time!

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151 episodes
Updated Sunday

Episodes151

Newest first

Aug 8, 2021 · 4 min
44- Point Mutations and Almonds
Point mutations can have a huge impact on the genome depending on where in the genetic code they occur. To illustrate this, we're going to be looking at a case study in the form of almonds- formerly poisonous nuts which had their metaphorical fangs taken out by a single base change... Sources for this episode: Hardy, E. R., Encyclopaedia Britannica (2021), Saint Basil the Great (online) [Accessed 22/05/2021]. Herron, J. C. and Freeman, S. (2015), Evolutionary Analysis (Fifth Edition, Global Edition). Harlow: Pearson Education Limited. Leman, J., Scientific American (2019), The Bitter Truth: Scientists Sequence the Almond Genome (online) [Accessed 18/05/2021]. Petruzzello, M., Encyclopaedia Britannica (2021), almond (online) [Accessed 18/05/2021]. Sánchez-Pérez, R., Pavan, S., Mazzeo, R., Molodovan, C., Cigliano, R. A., Del Cueto, J., Ricciardi, F., Lotti, C., Ricciardi, L., Dicenta, F., López-Marquéz, R. L. and Møller, B. L. (2019), Mutation of a bHLH transcription factor allowed almond domestication, Science 364(6445): 1095-1098. Author unknown, Wikipedia (date unknown), Almond (online) [Accessed 18/05/2021].
Aug 1, 2021 · 5 min
43- Two-Component Systems
Bacteria are far simpler in molecular terms than eukaryotes. However, they still need to be able to sense and respond to their environment. How do they do this? Enter the two-component system; a two-protein system which allows stimuli to be detected and gene expression altered using phosphate transfer. Sources for this episode: Madigan, M. T., Martinko, J. M., Dunlap, P. V. and Clark, D. P. (2009), Brock Biology of Microorganisms (12th Edition, International Edition), San Francisco: Pearson Benjamin Cummings Ltd. Thain, M. and Hickman, M. (2014), Dictionary of Biology (Eleventh Edition). London: Penguin Books Ltd. Willey, J. M., Sherwood, L. M. and Woolverton, C. J. (2017), Prescott's Microbiology (10th Edition, International Edition), Singapore: McGraw Hill Education Ltd. Author unknown, Wikipedia (date unknown), Osmotic concentration (online) [Accessed 27/05/2021].
Jul 25, 2021 · 6 min
42- The Quagga
No, the episode name isn't a typo. Rather, it's the name of a subspecies of zebra we're going to be discussing today. Along the way, we will explore clines, the purpose of zebra stripes and an attempt to breed back the quagga from its zebra cousins. Why don't we hear more about it? Well, because it no longer exists... Sources for this episode: Bryden, H. A. (1889), Kloof and karroo: Sport, legend and natural history in Cape Colony, with a notice of the game birds, and of the present distribution of antelopes and larger game, London and New York: Longmans, Green and Co. Available at: Internet Archive [Accessed 14/05/2021]. Cain, M. L., Bowman, W. D. and Hacker, S. D. (2011), Ecology (Second Edition). Sunderland, Massachusetts, Sinauer Associated Ltd. Davis, N., The Guardian (2019), Why the zebra got its stripes: to deter flies from landing on it (online) [Accessed 14/05/2021]. Douglas, G. (1821), A Communication of a Singular Fact in Natural History, Philosophical Transactions of the Royal Society of London (1776-1886) 111: 20–22. Available at Internet Archive [Accessed 14/05/2021]. The Editors, Encyclopaedia Britannica (2018), Quagga (online) [Accessed 14/05/2021]. Heywood, P. (2020), Sexual dimorphism of body size in taxidermy specimens of Equus quagga quagga Boddaert (Equidae), Journal of Natural History 53(45-46): 2757-2761. Author unknown, The Quagga Project (date unknown), Home (online) [Accessed 14/05/2021]. Author unknown, Wikipedia (date unknown), Quagga (online) [Accessed 14/05/2021].
Jul 18, 2021 · 6 min
41- Gruinard Island
Biological warfare has been around for centuries. However, it itself isn't the topic of today's episode. Rather, today we're going to talk about experiments conducted with anthrax on Gruinard Island in the United Kingdom. Sources for this episode: Johnson, M. P., Pye, S. and Allcock, L. (2008), Dispersal mode and assessments of recovery on the shores of Gruinard, the 'anthrax island', Biodiversity Conservation 17: 721-732. Madigan, M. T., Martinko, J. M., Dunlap, P. V. and Clark, D. P. (2009), Brock Biology of Microorganisms (12th Edition, International Edition), San Francisco: Pearson Benjamin Cummings Ltd. Riedel, S. (2004), Biological warfare and bioterrorism: a historical warfare, BUMC Proceedings 17: 400-406. Author unknown, BBC News (2001), Britain's 'Anthrax Island' (online) [Accessed 21/05/2021]. Author unknown, Gov.uk (date unknown), The Truth About Porton Down (online) [Accessed 21/05/2021]. Author unknown, Wikipedia (date unknown), Gruinard Island (online) [Accessed 26/04/2021].
Jul 11, 2021 · 3 min
40- Two Views on Communities
Today is more of a follow-up episode building on episode 39. Specifically, we're going to examine two different schools of thought about plant succession, known as the Gleasonian and Clementsian models... Sources for this episode: Cain, M. L., Bowman, W. D. and Hacker, S. D. (2011), Ecology (Second Edition). Sunderland, Massachusetts, Sinauer Associated Ltd. Hagen, J., Encyclopaedia Britannica (2020), Frederic Edward Clements (online) [Accessed 25/04/2021]. Author unknown, Wikipedia (date unknown), Henry A. Gleason (botanist) (online) [Accessed 25/04/2021].
Jul 4, 2021 · 5 min
39- Succession and Climax Communities
Our discussion this week is going to head back into ecology and focus on succession- a change in the species composition of a community across space or time. Sources for this episode: Cain, M. L., Bowman, W. D. and Hacker, S. D. (2011), Ecology (Second Edition). Sunderland, Massachusetts, Sinauer Associated Ltd. Thain, M. and Hickman, M. (2014), Dictionary of Biology (Eleventh Edition). London: Penguin Books Ltd. Thompson, J. N., Encyclopaedia Britannica (2018), Ecological succession (online) [Accessed 10/04/2021]. Author unknown, Encyclopaedia.com (updated 2018), Plagioclimax (online) [Accessed 10/04/2021].
Jun 27, 2021 · 5 min
38- Haemophilia
Haemophilia is a genetic condition which is characterised by one of the blood clotting factors, usually encoded for on the X chromosome, not being encoded for properly for various reasons- whether it's a mobile genetic element inserting itself into the gene or a simple mutation. On the show today, we describe the cause and symptoms of haemophilia, as well as using the case study of Queen Victoria to show that new mutations are a surprisingly common root cause... Sources for this episode: Francioli, L. C., et al. (2015), Genome-wide patterns and properties of de novo mutations in humans. Nature Genetics 47(7): 822- 826. Mannucci, P. M. and Tuddenham, E. G. D. (2001), The Haemophilias- From Royal Genes to Gene Therapy. The New England Journal of Medicine 344(23): 1773- 1779. Thain, M. and Hickman, M. (2014), Dictionary of Biology (Eleventh Edition). London: Penguin Books Ltd. Author unknown, The Haemophilia Society (date unknown), Bleeding Disorders > Haemophilia (online) [Accessed 08/04/2021]. Author unknown, Wikipedia (date unknown), Factor VIII (online) [Accessed 08/04/2021]. Author unknown, Wikipedia (date unknown), Queen Victoria (online) [Accessed 08/04/2021].
Jun 20, 2021 · 4 min
37- Metapopulations
We're all familiar with populations, but what about a metapopulation? Put simply, these are populations of populations. Thanks to our sources and also my interpretation of the subject from back when I studied the concept, that's the notion we're going to unravel today... Sources for this episode: Cain, M. L., Bowman, W. D. and Hacker, S. D. (2011), Ecology (Second Edition). Sunderland, Massachusetts, Sinauer Associated Ltd. Thompson, J. N., Encyclopaedia Britannica (2016), Metapopulation (online) [Accessed 17/04/2021]. Wu, J., Encyclopaedia Britannica (2019), Patch dynamics (online) [Accessed 18/04/2021]. In this episode, I use an analogy from how I understood the concept from back when I was taught the concept at university, which I've signposted.
Jun 13, 2021 · 7 min
36- Hardy-Weinberg Equilibrium
Back in the early 20th century, an English mathematician and a German scientist both independently came up with an equation to portray the frequency of different phenotypes in a hypothetical population. As we'll see today, this equation rests on some pretty big assumptions which effectively exclude evolution. Why is this useful? Well, because we can use it to see if evolution might be occurring... Sources for this episode: Chen, B., Cole, J. W. and Grond-Ginsbach, C. (2017), Departure from Hardy Weinberg Equilibrium and Genotyping Error. Frontiers in Genetics 8(167). Herron, J. C. and Freeman, S. (2015), Evolutionary Analysis (Fifth Edition, Global Edition). Harlow: Pearson Education Limited. TED-Ed, YouTube (2012), Five fingers of evolution- Paul Anderson (online) [Accessed 18/04/2021]. Thain, M., and Hickman, M. (2014), The Penguin Dictionary of Biology, 11th edition. London: Penguin Publishing Group. Author unknown, Wikipedia (date unknown), G. H. Hardy (online). Author unknown, Wikipedia (date unknown), Wilhelm Weinberg (online).
Jun 6, 2021 · 4 min
35- Five Kingdoms, Three Domains
Today, we're going to discuss classification. We're going to briefly skim over how people historically used to organise life, before the establishment of the prokaryote-eukaryote division which would stay in place until an American scientist called Carl Woese rocked the taxonomic boat... Sources for this episode: Craine, A. G., Encyclopaedia Britannica (2020), Carl Woese (online) [Accessed 10/04/2021]. Author unknown, Wikipedia (date unknown), Taxonomy (online) [Accessed 10/04/2021]. Some of the discussion is based on my previous education on the subject and my completion of a Massive Open Online Course 'Emergence of Life' covering this topic in 2018.
May 30, 2021 · 3 min
34- The Tuatara
On the show today, we discuss the tuatara- two (or possibly only one) species of reptile which are the final representatives of an ancient lineage. I didn't really go into it in the main episode, but there appears to be some debate about whether or not the tuatara is one species or two. All the sources I'd used in this week's episode list two species, but I afterwards discovered an article from the journal 'Conservation Genetics' which concluded that the tuatara should probably be thought of as one species instead of two. I might come back to it in a future episode. The paper in question is: Hay, J. M., Sarre, Stephen D., Lambert, D. M., Allendorf, F. W. and Daugherty, C. H. (2010), Genetic diversity and taxonomy: a reassessment of species designation in tuatara (Sphenodon: Reptilia), Conservation Genetics 11: 1063-1081. Sources for this episode: Blythe, C. A., Encyclopaedia Britannica (2021), New Zealand (online) [Accessed 28/03/2021]. Campbell, N. A., Urry, L. A., Cain, M. L., Wasserman, S. A., Minorsky, P. V. and Reece, J. B. (2018), Biology: a global approach, 11th edition (Global Edition), Harlow, Pearson Education Limited. Cooke, F., Dingle, H., Hutchinson, S., McKay, G., Schodde, R., Tait, N. and Vogt, R. (2008), The Encyclopedia of Animals: A Complete Visual Guide (p.370). Sydney: Weldon Owen Pty Ltd. Thain, M. and Hickman, M. (2014), Dictionary of Biology (Eleventh Edition). London: Penguin Books Ltd. Author unknown, Wikipedia (date unknown), Rhynchocephalia (online) [Accessed 28/03/2021].
May 23, 2021 · 3 min
33- Lethal Alleles
At A Level, we are taught that dominant: recessive traits are in a 3:1 ratio for any trait in which only one gene encodes for it. However, it's not always that simple. Enter lethal alleles... Sources for this episode: Gao, Z., Waggoner, D., Stephens, M., Ober, C. and Przeworski, M. (2015), An Estimate of the Average Number of Recessive Lethal Mutations Carried by Humans. Genetics 199: 1243- 1254. Roos, R. A. C. (2010), Huntingdon's disease: a clinical review. Orphanet Journal of Rare Diseases 2010 5:40. Author unknown, Wikipedia (date unknown), Lethal allele (online) [Accessed 26/03/2021]. Author unknown, Wikipedia (date unknown), Manx cat (online) [Accessed 27/03/2021].
May 16, 2021 · 5 min
32- Trisomies and Non-Disjunction
Usually, we get two copies of each chromosome. However, the finely tuned process of meiosis and fertilisation can go awry such that a new zygote ends up with three copies. Depending on the chromosome, this can have serious consequences... Sources for this episode: For an explanation of non-disjunction which I found helpful when I was at sixth form, see: Amoeba Sisters, YouTube (2017), Meiosis (Updated) (online) [Accessed 25/03/2021]. Xu, X., Zhang, X., Han, J.-W., Adamu, Y. and Zhang, B. (2020), Potential Increased Risk of Trisomy 18 Observed After a Fertilizer Warehouse Fire in Brazos County and TX. International Journal of Environmental Research and Public Health 17: 2561- 2571. Author unknown, NHS (date unknown), Edwards' syndrome (trisomy 18) (online) [Accessed 25/03/2021].
May 9, 2021 · 5 min
31- Choanoflagellates
We often think about animals as an insular group. However, as with any genetic grouping, animals do have close relatives. On the show today, we discuss choanoflagellates- considered the closest relatives to animals today, and possibly a good candidate for what the common ancestor of all animals would have looked like. Sources for this episode: Campbell, N. A., Urry, L. A., Cain, M. L., Wasserman, S. A., Minorsky, P. V. and Reece, J. B. (2018), Biology: a global approach, 11th edition (Global Edition), Harlow, Pearson Education Limited. The Editors, Encyclopaedia Britannica (2021), Choanoflagellate (online) [Accessed 13/03/2021]. Holland, S. M., Encyclopaedia Britannica (2021), Ordovician Period (online) [Accessed 13/03/2021]. Marshall, M., New Scientist (2009), Timeline: The evolution of life (online) [Accessed 13/03/2021]. Philippe, H., et al. (2009), Phylogenomics Revives Traditional Views on Deep Animal Relationships. Current Biology 19: 706- 712.
May 2, 2021 · 3 min
30- Measures of Diversity
Biodiversity is often mentioned as one concept in popular culture. However, it can be split into different components depending on who you ask. Today, we're going to explore two different ways of chopping biodiversity up. Sources for this episode: Cain, M. L., Bowman, W. D. and Hacker, S. D. (2011), Ecology (2nd edition). Sunderland: Sinauer Associates Ltd. Author unknown, Wikipedia (date unknown), Gamma diversity (online) [Accessed 06/03/2021]. There are ways of working out biodiversity values, which we won't discuss in this episode. For a formula for the Shannon-Weiner index of biodiversity (which I'm going to try and discuss in a future episode), see: Thain, M. and Hickman, M. (2014), Dictionary of Biology (Eleventh Edition). London: Penguin Books Ltd. For Simpson's biodiversity index, see: Fullick A., Locke, J. and Bircher, P. (2015), A Level Biology for OCR A. Oxford: Oxford University Press.
Apr 25, 2021 · 4 min
29- Sympatric Speciation
This week, we're going to discuss sympatric speciation- the counterpart to allopatric speciation where no physical barrier is needed. Sources for this episode: Campbell, N. A., Urry, L. A., Cain, M. L., Wasserman, S. A., Minorsky, P. V. and Reece, J. B. (2018), Biology: a global approach, 11th edition (Global Edition), Harlow, Pearson Education Limited. Thain, M., and Hickman, M. (2014), The Penguin Dictionary of Biology, 11th edition. London: Penguin Publishing Group. Author unknown, National Geographic (date unknown), Speciation (online) [Accessed 28/02/2021]. Author unknown, Understanding Evolution (date unknown), Sympatric speciation (online). Available at: 'berkeley.edu' [Accessed 28/02/2021].
Apr 24, 2021 · 4 min
Bonus- William Darwin's Development
Bonus episode! Today, I'm going to focus on a less well-known story from the Darwin family. Specifically, let's look at William Erasmus Darwin, the eldest child of the family. In 1877, Darwin published an article about his observations of William's development. Sources for this episode: Darwin, C. R. (1877), A biographical sketch of an infant. Scientific American Supplement 86: 1373- 1374 (online). Available at: Internet Archive [Accessed 25/03/2021]. Author unknown, Wikipedia (date unknown), William Erasmus Darwin (online) [Accessed 25/03/2021]. Author unknown, Wikipedia (date unknown), The Descent of Man (online) [Accessed 26/03/2021].
Apr 18, 2021 · 4 min
28- Speciation and the Great Wall of China
The Great Wall of China is one of the most imposing monuments humanity has ever created- after all, it's not for nothing that the claim goes around that you can see it from space. However, it's not just an effective barrier for humans. In fact, a 2003 study indicates that it's causing speciation in the region... Sources for this episode: Campbell, N. A., Urry, L. A., Cain, M. L., Wasserman, S. A., Minorsky, P. V. and Reece, J. B. (2018), Biology: a global approach, 11th edition (Global Edition), Harlow, Pearson Education Limited. The Editors, Encyclopaedia Britannica (2021), Great Wall of China (online) [Accessed 19/02/2021]. Oltermann, P., et al., The Guardian/Observer (2010), The Ancient World (booklet series), Day 6: China. Associated with the British Museum. Su, H., Qu., L.-J., He, K., Zhang, Z., Wang, J., Chen, Z. and Gu, H. (2003), The Great Wall of China: a physical barrier to gene flow? Heredity 90: 212- 219.
Apr 11, 2021 · 6 min
27- Twin Types
We're always taught that twins can either be identical or non-identical. But what is the basis for this? And is there ever a situation where twin type is not quite so binary? Sources for this episode: Davis, N., the Guardian (2019), Scientists stunned by discovery of 'semi-identical' twins (online) [Accessed 07/02/2021]. Author unknown, BBC (2019), Semi-identical twins 'identified for only the second time' (online) [Accessed 07/02/2021]. Author unknown, Wikipedia (date unknown), Twin (online) [Accessed 08/02/2021].
Apr 3, 2021 · 5 min
26- The Anthropocene
The term 'Anthropocene' (roughly translated as 'Age of Man') is a term that is sometimes thrown about on the radio or in science. But what is it exactly? As we'll see today, the concept itself is relatively simpler, but nailing down the specifics is somewhat harder than it seems... Sources for this episode: Ashley, S., National Trust (date unknown), What is the Anthropocene? (online) [Accessed 30/01/2021]. Author unknown, Encyclopaedia Britannica (2020), Anthropocene Epoch (online) [Accessed 30/01/2021]. Author unknown, Wikipedia (date unknown), Chinese industralization (online) [Accessed 02/02/2021].