Biopedia

An episode all about a suggested topic- the walrus! Let’s explore how one species used to many, and the challenges the sole surviving species faces in the modern day…

Sources for this episode:

TBA

WE DID IT! 100 episodes. It feels crazy to say that the beginning of Biopedia in late 2020 is four and a half years ago when this episode comes out. Thank you all so much for listening and I look forward to many more episodes to come!

To celebrate our milestone, we are discussing a milestone in biology- as voted for by you the community over on YouTube. Get ready for an outmoded theory about how bacteria emerge on food and huge names such as Louis Pasteur and Robert Koch!

Sources for this episode:

• Madigan, M. T., Bender, K. S., Buckley, D. H., Sattley, W. M. and Stahl, D. A. (2019), Brock Biology of Microorganisms (15th edition). Harlow: Pearson Education Limited.
• Pasteur, L. (1881), On the Germ Theory. Science os-2(62): 420-422.

Don’t worry, you have not in fact stumbled onto a physics podcast. However, the Laws of Thermodynamics do have a rather significant connection to evolutionary biology. This is because, at first glance, they appear to lead to a rather startling conclusion- life should not be able to evolve at all…

Sources for this episode:

• Berg, J. M., Tymoczko, J. L. and Stryer, L. (2007), Biochemistry (6th edition). New York: W. H. Freeman and Company.
• Herron, J. C., and Freeman, S. (2015), Evolutionary Analysis. Harlow: Pearson Education Ltd.
• Masanes, L. and Oppenheim, J. (2017), A general derivation and quantification of the third law of thermodynamics. Nature Communications 8: 14538.
• Ritchie, R. and Ghent, D. (2015), A Level Chemistry for OCR A. Oxford: Oxford University Press.

Quick correction: I call the episode on sibling species episode 37 in the audio, but it’s actually episode 47!

Way back in the early days of Biopedia, we discussed the concept of sibling species. Now, we’re talking about cryptic species. Are these the same concept? Well, as we will see today, it’s complicated…

Sources for this episode:

• Allaby, M. (editor) (2020), Oxford Dictionary of Zoology. Oxford: Oxford University Press.
• Bickford, D., Lohman, D. J., Sodhi, N. S., Ng, P. K. L., Meier, R., Winker, K., Ingram, K. K. and Das, I. (2007), Cryptic species as a window on diversity and conservation. TRENDS in Ecology and Evolution 22(3): 148-155.
• Herron, J. C., and Freeman, S. (2015), Evolutionary Analysis. Harlow: Pearson Education Ltd.
• Hine, R. (2019), A Dictionary of Biology (Oxford Quick Reference), 8th edition, Oxford, Oxford University Press.
• Author unknown, Wikipedia (date unknown), Species complex (online) (Accessed 25/07/2024).

2023 was a warm year. But let’s put it into context. To do that, a 2024 study looked at temperature and tree core data to assemble summer temperatures all the way back to 1 CE. As for the result- the title speaks for itself…

Sources for this episode:

• Bianchi, G. G., & McCave, I. N. (1999). Holocene periodicity in North Atlantic climate and deep-ocean flow south of Iceland. Nature, 397(6719): 515–517.
• Büntgen, U., Myglan, V. S., Ljungqvist, F. C., McCormick, M., Di Cosmo, N., Sigl, M., Jungclaus, J., Wagner, S., Krusic, P. J., Esper, J., Kaplan, J. O., de Vaan, M. A. C., Luterbacher, J., Wacker, L., Tegel, W., & Kirdyanov, A. V. (2016). Cooling and societal change during the Late Antique Little Ice Age from 536 to around 660 AD. Nature Geoscience, 9(3): 231–236.
• Dull, R. A., Southon, J. R., Kutterolf, S., Anchukaitis, K. J., Freundt, A., Wahl, D. B., Sheets, P., Amaroli, P., Hernandez, W., Wiemann, M. C., & Oppenheimer, C. (2019). Radiocarbon and geologic evidence reveal Ilopango volcano as source of the colossal ‘mystery’ eruption of 539/40 CE. Quaternary Science Reviews, 222: 105855.
• Dytham, C. (2011). Choosing and Using Statistics: A Biologist’s Guide (3rd ed.). Wiley-Blackwell.
• Esper, J., Torbenson, M. and Büntgen, U. (2024), 2023 summer warmth unparalleled over the past 2,000 years. Nature 631: 94-97.
• Goosse, H., Crespin, E., Dubinkina, S., Loutre, M.-F., Mann, M. E., Renssen, H., Sallaz-Damaz, Y., & Shindell, D. (2012). The role of forcing and internal dynamics in explaining the “Medieval Climate Anomaly.” Climate Dynamics, 39(12): 2847–2866.
• Graham, N. E., Ammann, C. M., Fleitmann, D., Cobb, K. M., & Luterbacher, J. (2011). Support for global climate reorganization during the “Medieval Climate Anomaly.” Climate Dynamics, 37(5–6): 1217–1245.
• Lamb, H. H. (1965). The early medieval warm epoch and its sequel. Palaeogeography, Palaeoclimatology, Palaeoecology, 1(1): 13–37.
• Lowe, J., & Walker, M. (2015). Reconstructing Quaternary Environments (3rd ed.). Routledge.
• Mann, M. E., Zhang, Z., Rutherford, S., Bradley, R. S., Hughes, M. K., Shindell, D., Ammann, C., Faluvegi, G., & Ni, F. (2009). Global Signatures and Dynamical Origins of the Little Ice Age and Medieval Climate Anomaly. Science, 326(5957): 1256–1260.
• Matthews, J. A., & Briffa, K. R. (2005). The ‘little ice age’: re‐evaluation of an evolving concept. Geografiska Annaler: Series A, Physical Geography, 87(1): 17–36.
• Shi, F., Sun, C., Guion, A., Yin, Q., Zhao, S., Liu, T., & Guo, Z. (2022). Roman Warm Period and Late Antique Little Ice Age in an Earth System Model Large Ensemble. Journal of Geophysical Research: Atmospheres, 127(16): e2021JD035832.

A bit of an unusual one this year- I was recently given a Dr Who book featuring Charles Darwin. So, let's examine the historical details of this novella and see how they represented Darwin. Have they done him justice?

Sources for this episode:

TBA

Your number of ancestors double every generation. Two parents, four grandparents, and so on. If we compare these numbers to the total number of people alive on the planet as we go back in time, what do we find? And what do researchers say on the subject?

Sources for this episode:

• Bell, S., Phys (2013), Researcher uses DNA to demonstrate just how closely everyone on Earth is related to everyone else (online) (Accessed 05/07/2024).
• Berger, B. M. (1960), How Long Is a Generation? The British Journal of Sociology 11(1): 10-23.
• Hershberger, S., Scientific American (2020), Humans Are All More Closely Related Than We Commonly Think (online) (Accessed 05/07/2024).
• Matsamura, S. and Forster, P. (2008), Generation time and effective population size in Polar Eskimos. Proceedings of the Royal Society B: Biological Sciences 275: 1501-1508.
• Murdock, N. H. (1998), Teenage Pregnancy. Journal of the National Medical Association 90(3): 135.
• Author unknown, Guiness World Records (date unknown), Oldest person to give birth (online) (Accessed 05/07/2024).
• Author unknown, Our World in Data (date unknown), Population, 10,000 BCE to 2021 (online) (Accessed 05/07/2024).

For a podcast which has talked several times before about global warming and climate change, we haven't addressed fossil fuels yet. So, let's redress that today!

Sources for this episode:

• Hine, R. S. (2019), Oxford Dictionary of Biology (8th edition). Oxford: Oxford University Press.
• Kalair, A., Abas, N., Saleem, M. S., Kalair, A. R. and Khan, N. (2020), Role of energy storage systems in energy transition from fossil fuels to renewables. Energy Storage 3: e135.
• Ritchie, R. and Gent, D. (2015), A Level Chemistry for OCR A. Oxford: Oxford University Press.
• Author uknown, The Ohio State University (date unknown), Life on Mars: The Future of Human Adventure- Exploring Mars as a Solution to Earth's Problems (online) (Accessed 28/06/2024).
• Author unknown, Our World in Data (date unknown) Fossil fuels (online) (Accessed 28/06/2024).
• Author unknown, UMCP Berkeley (date unknown), The Carboniferous Period (online) (Accessed 28/06/2024).

In episode 71, we treated a galactic cycle of about 220 million years as a unit of time with which to view evolution. Today, we'll be picking up where we left off and seeing the story through all the way to the end- or rather, the beginning…

Sources for this episode:

• Cox, B. and Cohen, A. (2013), Wonders of Life. London: HarperCollins Publishers.
• Emelyanov, V. V. (2001), Rickettsiaceae, Rickettsia-like Endosymbionts, and the Origin of Mitochondria. Bioscience Reports 21(1): 1-17.
• Herron, J. C., and Freeman, S. (2015), Evolutionary Analysis. Harlow: Pearson Education Ltd.
• Knoll, A. H. (2005), Life on a Young Planet: The First Three Billion Years of Evolution on Earth. Princeton: Princeton University Press.
• Thain, M. and Hickman, M. (2004), The Penguin Dictionary of Biology (11th edition). London: the Penguin Group.
• Wernegreen, J. J. (2012), Endosymbiosis. Current Biology 22(14): R555-R561.

In 1986, the nuclear power plant at Chernobyl- then in the USSR, now in Ukraine- experienced meltdown. This disaster is one of the worst in nuclear history. However, there are some biological consequences we should explore.

Sources for this episode:

• The Editors, Encyclopedia Britannica (2020), Chernobyl accident summary (online) (Accessed 29/05/2024).
• The Editors, Encyclopedia Britannica (2024), Half-life (online) (Accessed 31/05/2024).
• Ellegren, H., Lingren, G., Primmer, C. R. and Møller, A. P. (1997), Fitness loss and germline mutations in barn swallows breeding in Chernobyl. Nature 389: 593-596.
• Hine, R. S. (2019), Oxford Dictionary of Biology (8th edition). Oxford: Oxford University Press.
• Møller, A. P. and Mousseau, T. A. (2015), Strong effects of ionizing radiation from Chernobyl on mutation rates. Nature Scientific Reports 5: 8363.
• Weinberg, H. Sh., Korol, A. B., Kirzhner, V. M., Avivi, A., Fahima, T., Nevo, E., Shapiro, S., Rennert, G., Piatak, O., Stepanova, E. I. and Skvarskaja, E. (2001), Very high mutation rate in offspring of Chernobyl accident liquidators. Proceedings of the Royal Society B: Biological Sciences 268: 1001-1005.