S2E7: Symbiosis

Hi everyone, welcome back to the Entangled Bank Podcast! On today’s episode, your host Chetali and two special guests, Dr. Mulberry (Olivia) and Dr. Nick J (Nick) are going to be talking about the evolution of symbiosis and examples of several symbiotic relationships, and how they evolved or are maintained. We will be giving some insight on what symbiosis really is, the types of symbiosis, how endosymbiosis evolved, and we will also be paying particular attention to mutualism as one type of symbiosis. We focus on how endosymbiosis evolved and the ways in which it led to several speciation events and the acquisition of organelles such as the mitochondria and chloroplasts in eukaryotic cells.

To begin our podcast, we focus on the origin of the mitochondria and chloroplast by unpacking and analyzing the evolution of endosymbiosis and the degrees of endosymbiosis. We give the redefined types of endosymbiosis which includes primary, secondary and tertiary endosymbiosis and how that applies to the evolution of eukaryotic cells. Additionally, we also briefly talk about some hypothesis about the machinery used by organisms to acquire different organelles and how we have been able to understand those mechanisms by the use of phylogeny, genome sequencing data, and other alternative theories.

Moving along the lines of the how there are different types of symbiotic relationships: mutualism, parasitism, and commensalism, we focus mostly on examples of mutualism. Specifically, Dr. Mulberry who is a plant expert, talks about some interesting examples of some plant and fungi mutualism and also some plant and insect mutualistic relationships as well. Dr. Nick J gives some examples of mutualistic relationships between some bacteria and fungi. He also touches on how some mutualistic symbiosis can involve multiple levels of symbiosis. Overall, we also talk about how these relationships evolved and how they are maintained.

We hope you enjoy the podcast, and get to learn about some fun symbiotic relationships and how they evolved! :)  

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