Your Inner Fish Season 1 Episode 2 Your Inner Reptile

In the second episode of Your Inner Fish season 1, entitled Your Inner Reptile, host and evolutionary biologist Dr. Neil Shubin uncovers the connections between humans and reptiles. Building upon the premise that humans share common ancestors with other species, Shubin investigates how certain traits that were once essential for survival have been passed down through evolution and can still be seen in humans today.

The episode begins with Shubin discussing the similarities between reptiles and birds, and how both groups can be traced back to a common ancestor. He then introduces his team of researchers who will be helping him explore the inner workings of reptiles and their relation to humans. Together, they visit a reptile exhibit and observe various species such as snakes, turtles, and lizards.

The team then uses imaging technology to examine the skulls of various reptiles, including those of dinosaurs. Shubin explains the importance of the temporal fenestrae, or holes in the skull, which were once used for jaw muscles but now serve as a key distinguishing feature between reptiles and mammals. He also notes how the placement of the fenestrae affects the structure and movement of the jaw, which further highlights the connection between these traits and evolution.

Shubin then introduces a new subject: the development of limbs. He explains how fins evolved into limbs, and how the four-limbed tetrapods eventually led to the evolution of reptiles. The team visits a laboratory where they observe the development of reptile embryos and how limbs begin to form. Using the knowledge gained from this observation, they create a model of a reptilian leg, which allows the team to see exactly how these limbs move and work.

Next, the team moves on to discuss how reptiles regulate their body temperature. Shubin explains the concept of “ectothermy,” where body temperature is regulated by the surrounding environment rather than internal body processes. He also notes the importance of “behavioral thermoregulation,” or how reptiles use their behavior to regulate their body temperature. For example, they may bask in the sun or retreat to a shaded area.

To further investigate the connection between reptiles and humans, Shubin examines the reptilian brain. He compares the brain structure of reptiles to that of mammals, highlighting the differences and similarities between the two. He notes that while the reptilian brain is less complex than the mammalian brain, it still plays a vital role in many aspects of human behavior, such as regulating the autonomic nervous system and controlling basic reflexes.

Finally, the team investigates the fascinating topic of regeneration in reptiles. Shubin explains how certain species of reptiles, such as lizards, are able to regenerate lost limbs, tails, and even hearts. He notes that while humans cannot regenerate limbs, scientists are studying these reptilian species in the hopes of one day being able to apply this knowledge to regenerative medicine.

Throughout the episode, Shubin uses engaging visuals, animations, and 3D models to illustrate his points and make the complex concepts more accessible to viewers. He also utilizes interviews with experts and historical references to provide context and further understanding. By the end of the episode, viewers will have a greater appreciation for the connection between humans and reptiles, and how evolution has shaped the traits we possess today.