Inner+Fish+Homework+SS

Regarding the Article: What people owe fish: A Lot (1) Describe at least three important PHYSICAL traits in humans that were found in fish first. There are multiple important physical traits that exist in humans but were first found in fish. Three of these examples include the centralized brain, sense organs such as eyes and ears (that come in pairs), and a jaw structure (the mouth). Paired appendages- fins on either side of their body  (2) Describe a SOCIAL trait in humans that was found in fish first. A social trait that is in humans but was first found in fish is the establishment of ‘sophisticated’ relationships. Cooperation

(3) What is an African cichlid and what behavior do they have that resembles social behavior in humans. Describe. An African cichlid is a colorful freshwater fish from lake Tanganyika in Africa. One of the cichlid traits that resembles social behavior in humans is living in relatively large groups of 10. In this group are the breeding mates and a jumble of adults and adolescent fish that ‘for rent’ take care and nurture the mates’ babies. These ‘helper’ fish as they are called are often not related to the mates at all, but in return for raising babies, they are protected from their predators and have security. Embarrassing that fish are complex in their behavior.

(4) Why is it interesting that female guppies may go through menopause? It is an interesting fact that female guppies may go through menopause because this finding affects menopause among women (humans) in their later years of life. Menopause might have an indirect affect on the reason women live and survive beyond their reproductive life. Menopause: occurs when female body stops releasing eggs; no longer fertile after completing menopause 'Grandmother hypothesis': idea that females are still alive after menopause because they can raise the young. Guppies go through menopause, which could mean that it has been along for a really long time. (5) Which genes in humans shifted color during migration from one part of the world to another and also shift in color in fish? According to Dr. Shubin, “the vertebrate family tree is really a tree of fish”. This being said, like the process of fish, in particular, the stickleback, migrated from salt to fresh water and with that migration brought a change in skin pigmentation. It is a similar process in humans. The genes shifted as humans migrated across Earth. Evolutionary evidence indicates that the first humans were in Africa. As migration happened to more northern climates, there was 'less pressure' to have skin pigmentations. During evolutionary history, certain humans lost skin pigmentations. Changing pigmentation helps survival for camouflage purposes while it has been proposed that humans do not need the protection from the sun in more northern climates.

(6) What is the significance to human biology that fish are the oldest group of vertebrates? It is significant to human biology that fish are the oldest group of vertebrates because it means that fish have had over 550 million years to experiment with “body plans and strategies,” according to Dr. Shubin. All vertebrates have: head, teeth, etc...

(7) Competition and predation among fish species led to the evolution of two important physical traits found in humans. What are these two traits and how did competition and predation spur their evolution? Competition and predation among fish species led to the evolution of jaws and teeth, two very important physical traits found in humans. These traits were spurred by competition and predation as the teeth served as protection and allowed smaller fish to eat bigger fish and vice versa.

Regarding the NPR interview with the author of Your Inner Fish, Neil Shubin (8) What is unusual about the Tiktaalik? There are many unusual features about Titallik. These features include that Tiktaalik is a link between a fish and land animal. As an animal, it is between 4 feet and 9 feet long, has scales and webbing with a flat head that has eyes on the top. Tiktaalik has a neck and inside the fin are elements that match up with the human’s shoulders, elbows, wrists and palms. Advantage: crawl away from predators

(9) What bones in the "arm" of a Tiktaalik are also found in human arms? The bones in the ‘arm’ of Tiktaalik that are also found in human arms include the humorous, elbow joint, and two bones found in the forearm of humans. The human arm has eight bones altogether, four of which come from the Tiktaalik.

(10) Explain why a is hiccup a relic of our fish ancestors? The hiccup is a relic of our fish ancestors because the hiccup is actually the act of the closing of the epiglottis in the back of the throat. Upon the epiglottis closing, an irritation is caused, stemming a reaction in the brain stem, a pattern that was recently discovered in tadpoles. Tadpoles and other fish/land animals breathe(d) in the form of a ‘hiccup’.