The Darwin Times
They Don’t Make Homo sapiens Like They Use To
By: Sabra Cacho
Evolution isn’t just a part of scientific history millions of years ago it’s showing up in everyday life!
We’ve all gone to class hearing about evolution--how fish turned into amphibians, amphibians to reptiles, so on and so on. We rarely ever see or hear about evolution in our lifetime, but it is happening as we speak! We have adapted all the way from our jaws to our feet, and everywhere in between. As Jared Diamond says “Biology is the science. Evolution is the concept that makes biology unique.” No matter how advance we become you can always see evolution happening, and constantly try to be fit for our surroundings.
An example of recent evolutionary changes is getting goose bumps. When you are cold, frightened, angry, or in awe have you notice the hair rising feeling on your neck and arms? Many other animals, mammals to reptiles, get goose bumps for the exact same reason; just like a cat or dog’s hair stands up and the same reason porcupine’s quills raise when they feel threatened. In cold temperatures, the hair standing up feeling is actually the rising hair. The hair traps air between itself and skin. This creates a form of insulation and warmth for the body. In instances of fear, goose bumps make an animal appear slightly larger, to much larger, depending on the animal, to hopefully scare away the predator. Humans do not benefit much from goose bumps and they are basically a leftover reaction from our past relatives or a vestigial structure. When we were not clothed and needed to scare our natural enemy thick body hair was helpful, yet natural selection removed the thick hair. And because we no longer have hair we no longer have the need for Goosebumps it is now more of a mild annoyance to remind you how cold you really are.
Another example is Jacobson’s organ, a part of animal anatomy and it helps us discover a lot about human sexual history. Jacobson’s organ is in the nose cavity and is a unique “smell” sensory organ which finds a chemical that starts sexual desire or alarm detects food trails pheromones. This organ helps some animals track mate and also helps detect danger. Humans have a Jacobson’s organ at birth but through the toddler years and other early stages of life the organ’s abilities slow down and dwindle to the point where it becomes ultimately useless. Long ago humans use this organ to find trails to mates when communication was not present. We no longer need this organ because not only can we communicate, obviously, but people can “track mates” by going to chat rooms, and bars.
The plantaris muscle is the muscle that allows animals to grip and manipulating objects with their feet. Almost like a thumb on your feet, you can see many apes and other monkeys that are able to use their feet just as well as their hands. Humans have this muscle as well, but because it isn’t needed anymore it has become underdeveloped that it is often taken out by doctors and surgeons for reconstructive tissue in other parts of the body. The muscle is so unimportant and no longer needed to the human body that 9% of all humans are now born without it. We no longer have the need for this muscle since we have started to walk up right, and this extra muscle was specifically used for quadrepedal movement
The last example is the coccyx is the only thing humans have left over from their tail. Over time we lost the need for a tail because we no longer need to swing in trees. Yet we did not lose the need for the coccyx, a small bone at the end of the vertebra column, it now functions as a support and keeps structure for many different muscles. This helps support a person when they sit down and lean back. The coccyx also supports the position of the anus. This evolution shows how certain body parts switch from one in importance to another.
As you can see many evolutionary changes have happened to humans over the years. John Morley says “Evolution is not a force but a process. This quote greatly represents evolution, it is a process and it’s constantly going, whether it is right now or in the next 10 years. There will constantly be some form of evolution in humans, and all organisms. As you can see Homo sapiens aren’t made like they used to be.
Sites
http://listverse.com/2009/01/05/top-10-signs-of-evolution-in-modern-man/
http://www.brainyquote.com/quotes/keywords/evolution.html
http://www.brainyquote.com/quotes/keywords/evolution_2.html
http://i.livescience.com/images/070831_human_evolution_02.jpg
By: Sabra Cacho
Evolution isn’t just a part of scientific history millions of years ago it’s showing up in everyday life!
We’ve all gone to class hearing about evolution--how fish turned into amphibians, amphibians to reptiles, so on and so on. We rarely ever see or hear about evolution in our lifetime, but it is happening as we speak! We have adapted all the way from our jaws to our feet, and everywhere in between. As Jared Diamond says “Biology is the science. Evolution is the concept that makes biology unique.” No matter how advance we become you can always see evolution happening, and constantly try to be fit for our surroundings.
An example of recent evolutionary changes is getting goose bumps. When you are cold, frightened, angry, or in awe have you notice the hair rising feeling on your neck and arms? Many other animals, mammals to reptiles, get goose bumps for the exact same reason; just like a cat or dog’s hair stands up and the same reason porcupine’s quills raise when they feel threatened. In cold temperatures, the hair standing up feeling is actually the rising hair. The hair traps air between itself and skin. This creates a form of insulation and warmth for the body. In instances of fear, goose bumps make an animal appear slightly larger, to much larger, depending on the animal, to hopefully scare away the predator. Humans do not benefit much from goose bumps and they are basically a leftover reaction from our past relatives or a vestigial structure. When we were not clothed and needed to scare our natural enemy thick body hair was helpful, yet natural selection removed the thick hair. And because we no longer have hair we no longer have the need for Goosebumps it is now more of a mild annoyance to remind you how cold you really are.
Another example is Jacobson’s organ, a part of animal anatomy and it helps us discover a lot about human sexual history. Jacobson’s organ is in the nose cavity and is a unique “smell” sensory organ which finds a chemical that starts sexual desire or alarm detects food trails pheromones. This organ helps some animals track mate and also helps detect danger. Humans have a Jacobson’s organ at birth but through the toddler years and other early stages of life the organ’s abilities slow down and dwindle to the point where it becomes ultimately useless. Long ago humans use this organ to find trails to mates when communication was not present. We no longer need this organ because not only can we communicate, obviously, but people can “track mates” by going to chat rooms, and bars.
The plantaris muscle is the muscle that allows animals to grip and manipulating objects with their feet. Almost like a thumb on your feet, you can see many apes and other monkeys that are able to use their feet just as well as their hands. Humans have this muscle as well, but because it isn’t needed anymore it has become underdeveloped that it is often taken out by doctors and surgeons for reconstructive tissue in other parts of the body. The muscle is so unimportant and no longer needed to the human body that 9% of all humans are now born without it. We no longer have the need for this muscle since we have started to walk up right, and this extra muscle was specifically used for quadrepedal movement
The last example is the coccyx is the only thing humans have left over from their tail. Over time we lost the need for a tail because we no longer need to swing in trees. Yet we did not lose the need for the coccyx, a small bone at the end of the vertebra column, it now functions as a support and keeps structure for many different muscles. This helps support a person when they sit down and lean back. The coccyx also supports the position of the anus. This evolution shows how certain body parts switch from one in importance to another.
As you can see many evolutionary changes have happened to humans over the years. John Morley says “Evolution is not a force but a process. This quote greatly represents evolution, it is a process and it’s constantly going, whether it is right now or in the next 10 years. There will constantly be some form of evolution in humans, and all organisms. As you can see Homo sapiens aren’t made like they used to be.
Sites
http://listverse.com/2009/01/05/top-10-signs-of-evolution-in-modern-man/
http://www.brainyquote.com/quotes/keywords/evolution.html
http://www.brainyquote.com/quotes/keywords/evolution_2.html
http://i.livescience.com/images/070831_human_evolution_02.jpg
The evolutionary benefit of the hammerhead shark
by Valeria Van Zyl
One day, while I was on the job of taking photographs of sea-creatures for advertisements about sea-world, I began to think of why hammerhead sharks had such oddly shaped heads. There had to be some reason as to why their heads stretched out farther than their body and their eyes were on two different sides of their head. After my trip under the water to take pictures I began to research and ask questions to fellow marine biologists about why their heads where so strangely shaped. Some people may think they are ugly, while others may find its irregular shape to be beautiful.
Ever wonder why these sharks have such strange shaped heads? These heads provide more benefit in hunting than that of the normal shape of the sharks head. The long football shaped head helps the shark to pin down its prey and also gives it a better field of vision. The head also makes the shark more buoyant enabling it to swim with ease.
Having eyes on both sides of its head gives the shark a 360 degree view of its environment. This boosts the ability of the shark to capture its prey accurately and more quickly.
The separation of nostrils gives the shark the ability to sense prey from a longer distance from that of a normal headed shark. Sensory organs on the hammerhead’s nose called ampullae of Lorenzini helps the shark to identify electrical fields. The electrical field helps the shark to know if there is prey moving even if it cannot see it. This increases its ability to find camouflaged prey hiding on the ocean floor. Also, this sense is 10 xs more effective than that of a shark with a normal head shape.
The hearing of a hammerhead shark is highly developed. They are able to hear low vibrations made frequently by wounded fish. This gives them an advantage to finding their prey.
Sharks were found during the late Paleozoic era. Geneticist Andrew Martin helped come up with this conclusion that the wing head shark was the first hammerhead shark to appear. Over time it passed on its genes with the advantage of having a wider head. The head was so beneficiary that the shark continued to undergo mutations and eventually they evolved much wider heads. Beauty is in the eye of the beholder. There are more benefits to a shark for having a hammerhead than having a normal shaped head. If I were a shark, I would definitely want to be a hammerhead.
Works Cited
Barley, Shanta. "Why the Hammerhead Shark Got Its Hammer - Life - 27 November 2009 - New Scientist." Science News and Science Jobs from New Scientist - New Scientist. 27 Nov. 2009. Web. 14 May 2010. <http://www.newscientist.com/article/dn18210-why-the-hammerhead-shark-got-its-hammer.html>.
DeStefano, David. "Biogeography of Hammerhead Shark." Redirect. Web. 14 May 2010. <http://bss.sfsu.edu/geog/bholzman/courses/Fall01%20projects/hammerhead%20web%20page.htm>.
Martin, Aidan R. "Origin and Evolution of the "Hammer"" ReefQuest Centre for Shark Research Home. Web. 14 May 2010. <http://www.elasmo-research.org/education/topics/d_hh_origin.htm>.
Morse, Len. "Physical Characteristics of the Hammerhead Shark - by Len Morse - Helium." Helium - Where Knowledge Rules. Web. 14 May 2010. <http://www.helium.com/items/1162880-hammerhead-shark-head-eyes-physical>.
Urmann, David H. "Hammerhead Sharks: Advanced Evolutionary Creatures." ArticleSnatch Free Article Directory. Web. 14 May 2010. <http://www.articlesnatch.com/Article/Hammerhead-Sharks--Advanced-Evolutionary-Creatures/511491>.
by Valeria Van Zyl
One day, while I was on the job of taking photographs of sea-creatures for advertisements about sea-world, I began to think of why hammerhead sharks had such oddly shaped heads. There had to be some reason as to why their heads stretched out farther than their body and their eyes were on two different sides of their head. After my trip under the water to take pictures I began to research and ask questions to fellow marine biologists about why their heads where so strangely shaped. Some people may think they are ugly, while others may find its irregular shape to be beautiful.
Ever wonder why these sharks have such strange shaped heads? These heads provide more benefit in hunting than that of the normal shape of the sharks head. The long football shaped head helps the shark to pin down its prey and also gives it a better field of vision. The head also makes the shark more buoyant enabling it to swim with ease.
Having eyes on both sides of its head gives the shark a 360 degree view of its environment. This boosts the ability of the shark to capture its prey accurately and more quickly.
The separation of nostrils gives the shark the ability to sense prey from a longer distance from that of a normal headed shark. Sensory organs on the hammerhead’s nose called ampullae of Lorenzini helps the shark to identify electrical fields. The electrical field helps the shark to know if there is prey moving even if it cannot see it. This increases its ability to find camouflaged prey hiding on the ocean floor. Also, this sense is 10 xs more effective than that of a shark with a normal head shape.
The hearing of a hammerhead shark is highly developed. They are able to hear low vibrations made frequently by wounded fish. This gives them an advantage to finding their prey.
Sharks were found during the late Paleozoic era. Geneticist Andrew Martin helped come up with this conclusion that the wing head shark was the first hammerhead shark to appear. Over time it passed on its genes with the advantage of having a wider head. The head was so beneficiary that the shark continued to undergo mutations and eventually they evolved much wider heads. Beauty is in the eye of the beholder. There are more benefits to a shark for having a hammerhead than having a normal shaped head. If I were a shark, I would definitely want to be a hammerhead.
Works Cited
Barley, Shanta. "Why the Hammerhead Shark Got Its Hammer - Life - 27 November 2009 - New Scientist." Science News and Science Jobs from New Scientist - New Scientist. 27 Nov. 2009. Web. 14 May 2010. <http://www.newscientist.com/article/dn18210-why-the-hammerhead-shark-got-its-hammer.html>.
DeStefano, David. "Biogeography of Hammerhead Shark." Redirect. Web. 14 May 2010. <http://bss.sfsu.edu/geog/bholzman/courses/Fall01%20projects/hammerhead%20web%20page.htm>.
Martin, Aidan R. "Origin and Evolution of the "Hammer"" ReefQuest Centre for Shark Research Home. Web. 14 May 2010. <http://www.elasmo-research.org/education/topics/d_hh_origin.htm>.
Morse, Len. "Physical Characteristics of the Hammerhead Shark - by Len Morse - Helium." Helium - Where Knowledge Rules. Web. 14 May 2010. <http://www.helium.com/items/1162880-hammerhead-shark-head-eyes-physical>.
Urmann, David H. "Hammerhead Sharks: Advanced Evolutionary Creatures." ArticleSnatch Free Article Directory. Web. 14 May 2010. <http://www.articlesnatch.com/Article/Hammerhead-Sharks--Advanced-Evolutionary-Creatures/511491>.
