106- Mitochondrial Eve and Y-Chromosomal Adam

Adam and Eve, Ask and Embla, Deucalion and Pyrrha… The cultures of the world seemingly love the idea of humanity descending from two founders. While this notion may not be in line with scientific thought, there are two individuals who everyone can trace either maternal or paternal ancestry to. Say hello to mitochondrial Eve and Y-chromosomal Adam…

Sources for this episode:

  • Berta, P., Hawkins, J. R., Sinclair, A. H., Taylor, A., Griffiths, B. L., Goodfellow, P. N. and Fellous, M. (1990), Genetic evidence equating SRY and the testis-determining factor. Nature 348: 448- 450.
  • Callaway, E. (2013), Nature News, Genetic Adam and Eve did not too far apart in time (online). (Accessed 18/10/2020).
  • Chan, E. K. F., Timmermann, A., Baldi, B. F., Moore, A. E., Lyons, R. J., Lee, S.-S., Kalsbeek, A. M. F., Petersen, D. C., Rautenbach, H., Förtsch, H. E. A., Bornman, M. S. R. and Hayes, V. M. (2019), Human origins in a southern African palaeo-wetland and first migrations. Nature 575: 185- 189.
  • Chiaroni, J., Underhill, P. A. and Cavalli-Sforza, L. L. (2009), Y chromosome diversity, human expansion, drift and cultural evolution. Proceedings of the National Academy of Sciences of the United States of America 190(48): 20174- 20179.
  • Fleischmann, T. (2019), The Norse Creation of the Cosmos. MFA, Salem Press Encyclopedia of Literature.
  • Fry, S. (2017), Mythos: The Greek Myths Retold. London: Michael Joseph Ltd (part of Penguin).
  • Ingman, M., Kaessmann, H., Pääbo, S. and Gyllensten, U. (2000), Mitochondrial genome variation and the origin of modern humans. Nature 408: 708- 713.
  • Nass, M. M. K. and Nass, S. (1963), Intramitochondrial fibers with DNA characteristics. The Journal of Cell Biology 10: 593- 611.
  • Sykes, B. (2001), The Seven Daughters of Eve. London: Corgi Books (part of the Random House Group Ltd.
  • Thain, M. and Hickman, M. (2004), The Penguin dictionary of biology, 11th edition, London, Penguin Books Ltd.
  • Author unknown (2010), Holy Bible: International Children’s Bible (New Century Version). Milton Keynes: Authentic Media Limited.

105- Former Estimates of Earth’s Age

We know today that our planet Earth is billions of years old. However, the people of a few centuries ago would have been equally convinced it was only a few thousand years old. So what were some of these old ages, and how big a shift is it from there to the age we’ve arrived at today?

Sources for this episode:

TBA

103- The Gaia Hypothesis

Tackling James Lovelock's most famous theorem is no easy task. However, that's exactly what we're going to do today. Join us for a breakdown of the Gaia Hypothesis, a discussion of altruism, a throwback to the Black Queen Hypothesis in episode 21 and some speculation based on an early 2000s book by Lovelock himself.

Sources for this episode:

TBA

102- Hyperdontia and Hypodontia

As it turns out, Louis XIII of France and Drypetina of Pontus have something in common. They have hyperdontia, or too many teeth. Today, we go through the phenomena of hyperdontia, hypodontia and concomitant hypo-hyperdontia.

Sources for this episode:

  • Ammianus Marcellinus (1956) in Three Volumes (Vol. I). Translated by J. C. Rolfe. Cambridge, Massachusetts and London: Harvard University Press and William Heinemann Ltd.
  • Eshgian, N., Al-Talib, T., Nelson, S. and Abubakr, N. H. (2021), Prevalence of hyperdontia, hypodontia, and concomitant hypo-hyperdontia. Journal of Dental Sciences 16: 713-717.
  • Gracco, A. L. T., Zanatta, S., Valvecchi, F. F., Bignotti, D., Perri, A. and Baciliero, F. (2017), Prevalence of dental agenesis in a sample of Italian orthodontic patients: an epidemiological study. Progress in Orthodontics 18:33.
  • Littlewood, I. (2002), The Rough Guide: History of France. London: Rough Guides Ltd.
  • Peker, I., Kaya, E. and Darendeliler-Yaman, S. (2009) Clinical and radio- graphical evaluation of non- syndromic hypodontia and hyperdontia in permanent dentition. Medicina Oral Patologia Oral y Cirugia Bucal 14: e393e7.
  • Pliny (1961), Natural History in Ten Volumes (Volume II: Libri III- VII). Translated by H. Rackham. Cambridge, Massachusetts and London: Harvard University Press and William Heinemann, Ltd.
  • Snow, P. and Macmillan, A. (2022), Kings & Queens: The Real Lives of the English Monarchs. London: Welbeck.
  • Author unknown (1830), A Collection of the Most Instructive and Amusing Lives Ever Published. Volume VIII: Lord Herbert and Prince Eugene. London: Whittaker, Treacher, and Arnot.
  • Author unknown, Wikipedia (date unknown), Agrippina the Younger (online) (Accessed 15/10/2024).
  • Author unknown, Wikipedia (date unknown), Drypetina (online) (Accessed 15/10/2024).
  • Author unknown, Wikipedia (date unknown), Louis XIII (online) (Accessed 15/10/2024).

100- Germ Theory and Spontaneous Generation

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.

99- The Laws of Thermodynamics in Evolution

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.

98- Cryptic Species

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).

97- The Hottest Summer in 2000 Years

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.