71- Galactic Cycles in Evolutionary History

It takes our sun 220 million years to orbit around the middle of our home galaxy. But that kind of timescale can be difficult to picture. So, using the International Stratigraphy Chart as a guidance for what different time periods mean in terms of millions of years, let's zoom out to the scale of a galactic year and see what happened in Earth's prehistory one cycle ago, two and so on.

Sources for this episode:

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  • Cohen, K. M., Finney, S. C., Gibbard, P. L. and Fan, J.-X. (2013; updated). The ICS International Chronostratigraphic Chart. Episodes 36: 199-204.
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70- The Microbiome and Microbiota

Most people will have come across this term before, but what does it actually mean? Today, we'll be dissecting the terms microbiome and microbiota and looking at what can impact them.

Sources for this episode:

  • Amon, P. and Sanderson, I. (2017), What is the microbiome? Archives of Disease in Childhood- Education and Practice 102-258-261.
  • Cremon, C., Barbaro, M. R., Ventura, M. and Barbara, G. (2018), Pre- and probiotic overview. Current Opinion in Pharmacology 43: 87-92.
  • Kim, H., Sitarik, A. R., Woodcroft, K., Johnson, C. C. and Woratti, E. (2019), Birth Mode, Breastfeeding, Pet Exposure and Antibiotic Use: Associations With the Gut Microbiome and Sensitization in Children. Current Allergy and Asthma Reports 19: 22.
  • Mariat, D., Firmesse, O., Levenez, F., Guimarăes, V. D., Sokol, H., Doré, J., Corthier, G. and Furet, J.-P. (2009), The Firmicutes:Bacteroidetes ratio of the human microbiota changes with age. BMC Microbiology 9:123.
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  • Rees, T., Bosch, T. and Douglas, A. E. (2018), How the microbiome challenges our concept of self. PLoS Biology 16(2): e2005358.
  • Sender, R., Fuchs, S. and Milo, R. (2016), Revised estimates for the number of human and bacteria cells in the body. PLoS Biology 14(8): e1002533.
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Island Folk 3- Saint Helena and Anthropogenic Impact

Saint Helena is an island in the middle of the Atlantic Ocean, perhaps most famous as the final residence of Napoleon I, Emperor of the French from 1804 to 1814 and again briefly in 1815. However, there is also plenty of interesting ecology and anthropogenic impact to talk about. Join myself and my co-host on an old episode of Island Folk to find out more!

The episode can be found at the following link: https://open.spotify.com/episode/1yP66nlH0ReAaZUWETXEHp?si=e894e255600c4bc0

Hope you enjoy!

69- Punctuated Equilibrium, Phyletic Gradualism and Creationist Philosophy

This episode discusses what it says on the tin- two different models of the pace at which evolution happens. Punctuated equilibrium comes to us courtesy of Niles Eldredge and Steve Gould in the 1970s. We won't do a deep dive on which model is considered correct in this episode. However, punctuated equilibrium was appropriated by creationists in the 1980s as this issue became political- leading us to a convenient tangent on what exactly creationist philosophy is.

Sources TBA.

68- Mammoths and the Pyramids

Woolly mammoths are an iconic feature of the Ice Age in popular imagination. However, on today's episode, we will also see that they are the basis of a fun fact that may change your perception of the past…

Sources for this episode:

  • Ashman, D., Nature (2000), The sky was the limit for the Pyramid builders (online) [Accessed 10/10/2023].
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67- Mythological Hybrids and Chromosome Count

A throwaway comment on Big Bang Theory got me thinking- could hybrid animals such as the griffin and the hippogriff be possible from a biological viewpoint? Using these two examples, we will explore the chromosome number of hybrid animals and see what it means for our mythical friends…

Sources for this episode:

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Introducing- Autocrat

Introducing my newest venture- being one half of the Autocrat podcast! Autocrat is a podcast which aims to explore Roman civilisation from beginning to end. Beginning with the mythology and the stories of Aeneas and Romulus, the podcast will trace the journey through the Roman Kingdom, the Republic, the Empire and all the way to 1453 and beyond. Who knows if we'll make it that far, but we hope to have fun with it!

The podcast can be found at https://open.spotify.com/show/30Muilr1O66yA4UDcj76SW?si=891136d533c446a5 or on YouTube at youtube.com/@autocratpodcast. If the show sounds fun, feel free to come and join us!

66- The KT Extinction

It's episode 66, so I thought I'd cover a big event from 66 million years ago- the death of the dinosaurs! But it's not all doom and gloom- we will also take a look at how to prevent asteroid impacts in future.

Sources for this episode: 1) Bottke, W. F., Vokrouhlický, D. and Nesvorný, D. (2007), An asteroid breakup 160 Mya as the probable sources of the K/T impactor. Nature 449: 48-53. 2) Brusatte, S. (2018), The Rise and Fall of the Dinosaurs: The Untold Story of a Lost World. London: Picador. 3) Chapman, C. R. (2004), The hazard of near-Earth asteroid impacts on earth. Earth and Planetary Science Letters 222: 1-15. 4) Chapman, C. R. and Morrison, D. (1994), Impacts on the Earth by asteroids and comets: assessing the hazard. Nature 367: 33-40. 5) Cohen, K. M., Finney, S. C., Gibbard, P. L. and Fan, J.-X. (2013, updated), The ICS International Chronostratigraphy Chart. Episodes 36: 199-204. 6) Dodson, P. (1990), Counting dinosaurs: how many kinds were there? Proceedings of the National Academy of Sciences of the United States of America 87(19): 7608- 7612. 7) The Editors, Encyclopedia Britannica (2023), sublimation
(online) [Accessed 29/07/2023]. 8) Ostrom, J. H. and Padian, K., Encyclopedia Britannica (2023), dinosaur (online) [Accessed 14/07/2023]. 9) Pope, K. O., Baines, K. H., Ocampo, A. C. and Ivanov, B. A. (1994), Impact winter and the Cretaceous/Tertiary extinctions: Results of a Chicxulub asteroid impact model. Earth and Planetary Science Letters 128: 719- 725. 10) Schulte, P., Alegret, L., Arenillas, I., Arz, J. A., Barton, P. J., Brown, P. R., Barlower, T. J., Christeson, G. L., Claeys, P., Cockell, C. S., Collins, G. S., Deutsch, A., Goldin, T. J., Goto, K., Grajales Nishmura, J. M., Grieve, R. A. F., Gulick. S. P. S., Johnson, K. R., Kiessling, W., Koeberl, C., Kring, D. A., MacLeod, K. G., Matsui, T., Melosh, J., Montanari, A., Morgan, J. V., Neal, C. R., Nichols, D. J., Norrison, R. D., Pierazzo, E., Ravizza, G., Rebolledo-Vieyra, M., Reimold, W. U., Robin, E., Salge, T., Speijer, R. P., Sweet, A. R., Urrutia-Fucugauchi, J., Vajida, V., Whalen, M. T. and Willumsen, P. S. (2010), The Chicxulub Asteroid Impact and Mass Extinction at the Cretaceous-Palaeogene Boundary. Science 327(5970): 1214- 1218. 11) Starrfelt, J. and Liow, L. H. (2016), How many dinosaur species were there? Fossil bias and true richness estimated using a Poisson sampling model. Philosophical Transactions of the Royal Society B: Biological Sciences 371(1691): 20150219. 12) Yousuf, I., Encyclopedia Britannica (2023), Empire State Building (online) [Accessed 27/07/2023].

65- The Fermi Paradox and the Great Filter

Enrico Fermi is the man behind today’s episode, as we’re going to talk all about the Fermi paradox. In essence, why do we not see anyone else out there in the universe besides ourselves? Well, a number of solutions have been proposed- and they have to do with the second concept in today’s episode: the Great Filter.
Sources for this episode: 1) Bailey, M. M. (2023), Could AI be the Great Filter? What Astrobiology can Teach the Intelligence Community about Anthropogenic Risks. arXiv preprint arXiv:2305.05653. 2) Borger, J., the Guardian (2022), Cuban missile crisis 60 years on: new papers reveal how close the world came to nuclear disaster (online) [Accessed 08/07/2023]. 3) Buser, R. (2000), The Formation and Early Evolution of the Milky Way Galaxy. Science 287(5450): 69-74. 4) The Editors of Scientific American (2015), Exoplanets: Worlds Without End. New York: Scientific American. 5) Laughlin, R. B. and Pines, D. (2000) The Theory of Everything. Proceedings of the National Academy of Sciences of the United States of America 97(1): 28-31. 6) Raschky, P. A. and Wang, L. C. (2017), Reproductive behaviour at the end of the world: the effect of the Cuban Missile Crisis on U.S. fertility. Applied Economics 49(56): 5722- 5727. 7) Re, F. (2022), Can the Theory of Everything be the Great Filter? 8) Stern, S. M. (2005), The Week the World Stood Still: Inside the Secret Cuban Missile Crisis. Stanford, California: Stanford University Press. 9) Author unknown, NASA (date unknown), Hubble’s New Shot of Proxima Centauri, our Nearest Neighbour (online) [Accessed 09/07/2023]. 10) Author unknown, NASA Exoplanet Exploration (date unknown), Largest Batch of Earth-size Habitable Zone Planets Found Orbiting TRAPPIST-1 (online) [Accessed 09/07/2023]. 11) Author unknown, Wikipedia (date unknown), Parsec (online) [Accessed 08/07/2023]. 12) Author unknown, Wikipedia (date unknown), Tau Ceti (online) [Accessed 09/07/2023].