Tiktaalik is a fish that lived 375 million years ago that grew to three metres long and had aquatic features mixed with others more suited to life on land. The fossils of five Tiktaalik specimens reveal that the animals had a large, robust pelvic girdle, a prominent hip joint, and long hind fins. The powerful fins could have propelled the beast in the water, but also helped it walk on riverbeds, or scramble around on mudflats. It is believed that Tiktaalik evolved into four- legged land animals. The scientists have yet to find a Tiktaalik hind fin bone, or any remains that might shed light on the origins of toes. A picture of Tiktaalik is available at https://www.npr.org/2010/07/05/127937070/t human-edge-finding-our-inner-fish Describe how Darwin would explain that evolution of hind legs (of land animals) actually began as enhanced hind fins (of Tiktaalik), referring to his relevant observations and inferences (Lecture 02 History of Evolutionary Thought - slide 18). Indicate where the observations and inferences are illustrated in your answer.

Tiktaalik is a fish that lived 375 million years ago that grew to three metres long and had aquatic features mixed with others more suited to life on land. The fossils of five Tiktaalik specimens reveal that the animals had a large, robust pelvic girdle, a prominent hip joint, and long hind fins. The powerful fins could have propelled the beast in the water, but also helped it walk on riverbeds, or scramble around on mudflats. It is believed that Tiktaalik evolved into four- legged land animals. The scientists have yet to find a Tiktaalik hind fin bone, or any remains that might shed light on the origins of toes. A picture of Tiktaalik is available at https://www.npr.org/2010/07/05/127937070/t human-edge-finding-our-inner-fish Describe how Darwin would explain that evolution of hind legs (of land animals) actually began as enhanced hind fins (of Tiktaalik), referring to his relevant observations and inferences (Lecture 02 History of Evolutionary Thought - slide 18). Indicate where the observations and inferences are illustrated in your answer.

Concepts of Biology

1st Edition

ISBN:9781938168116

Author:Samantha Fowler, Rebecca Roush, James Wise

Publisher:Samantha Fowler, Rebecca Roush, James Wise

Chapter15: Diversity Of Animals

Section: Chapter Questions

Problem 3ACQ: Figure 15.33 Which of the following statements about common features of chordates is true? a. The...

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