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Evolution Unit Project: Green Sea Turtles

For my biology class.

Matthew Nguyen

on 22 May 2014

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Transcript of Evolution Unit Project: Green Sea Turtles

Evolution Unit Project: Green Sea Turtles (Chelonia mydas)
A Hawaiian green sea turtle's diet as a hatchling is omnivorous, whereas the adult diet is mainly herbivorous. Their hatchling/juvenile diet includes invertebrates like crabs, jellyfish, sponges, squids as well as flora like algae and phytoplankton. As adults, their diets are mostly algae, seagrass, and seaweed. Their serrated beaks allow them to tear apart seagrass and scrape algae off of rocks. However, adults do occasionally consume other marine life, such as jellyfish.

The green sea turtle shares a mutualistic relationship with the yellow tang and other cleaner fish. By cleaning the sea turtle's shell of algae and parasites, the fish receive nourishment while the sea turtle receives a cleaner shell and improved health.

The main predators of Hawaiian green sea turtles are large tiger sharks and other predatory fish. Humans also constitute as a threat. Eggs and hatchlings, however, are more susceptible to lesser predators such as crabs and seabirds. Another fatal hazard for these Hawaiian turtles is a tumorous disease known as fibropapillomatosis. The disease's definite cause is unknown.

Green sea turtles are constantly swimming and will occasionally seek shelter to sleep. They will either sleep at the surface over deep water or under coral reefs/rocks.
Four adaptations of the Hawaiian green sea turtle include beak shape, diet, predetermined clutch size, and shell coloring.

The beak shape of a sea turtle is vital for it's diet as well as how efficiently it can gather food. For the green sea turtle, the degree of serration of its beak can grant more opportunities to gather food from difficult to graze areas. Some individuals may have a rounder beak to graze off of rocks easier while others have sharper beaks in order to tear seagrass quicker.

Thanks to it's diet, the Hawaiian green sea turtle can rely on the fauna of it's surroundings as usually a consistent food source. While other species of marine turtles may hunt for their prey, an herbivorous diet allows a lesser risk of starvation, assuming plant life is plentiful in the ecosystem.
Variations in Traits
When female green sea turtles must lay their eggs at their natal beaches, there are many predators who will prey on the eggs or hatchlings . To partially prevent this, she conceals them under the sandy surface. Still, many eggs fall victim to predators. A female who is genetically predisposed to more offspring will often have more surviving successors. As the clutch of a green sea turtle may range anywhere from one-hundred to
two-hundred eggs, the more eggs there are, the greater chance of passing down her and the father's genes.

A Hawaiian green sea turtle's shell coloring can range from a mottled olive to brown to almost black. Depending on the habitat of the sea turtle, the coloration varies. For example, an olive colored shell would be more common in a habitat of a seagrass bed.
Variations in Traits
If a massive eruption were to occur from the volcanoes of Hawaii, it would drastically reduce the food reservoir and alter the habitat of the green sea turtle. For example, the ash, soot, and lava would ravage the surrounding fauna. Since the adult population of the green sea turtles are herbivores, many would starve and die out.

As the lava met the ocean, a black sand beach could potentially be created. The beaches and shorelines encompassing the volcanic eruption would turn into a sooty, onyx color. When the lava cooled down, the environment would be a petrified, rugged terrain. This would be especially detrimental for the females whose natal beach is near the volcanic eruption. Due to the harsh and jagged territory, it would be laborious to conceal the eggs here. There's a good possibility that some female Hawaiian green sea turtles would stop reproducing here.
Disaster: Volcanic Eruption
Since the remaining environment would be rocky, the Hawaiian green sea turtles with the rounder beaks would have a less difficult time scraping algae off of rocks without wounding themselves. There would be more algae than seagrass or seaweed (since algae is a pioneer species), giving a rounder beak for grazing more priority over a sharper beak for tearing.

As the individuals who could not adapt their diet to the disaster starved off, individuals who could shift their herbivore centered diet to a more omnivorous one, like the diet they had as a juvenile, would reduce their probability of starvation due to increasing their channels of nourishment.
Surviving Adaptations - Post Disaster
Considering the beaches are now rugged and are difficult to conceal eggs in, remaining predators now have greater access to preying on the green sea turtle's eggs. Females who are genetically predisposed to produce clutches of up to two-hundred eggs or more have the likeliest chance of having any surviving offspring.

The shell coloration of an individual is now more significant than ever. Thanks to the darkened environment, including the polluted water, an almost black shell serves the most adequate camouflage against lingering predators.

Natural selection dictates that individuals best suited to their environment often persevere and reproduce the most. Hawaiian green sea turtles, after a volcanic eruption, with round beaks and omnivorous diets would suffer from starvation the least. Those who could produce the highest quantity of eggs in a clutch would often have the optimal percentage of surviving offspring. Individuals with the darkest shell had the best camouflage in the murky ecosystem. Over time, descendents of ancestors bearing these four traits would be unparalleled to others in their ecosystem in terms of fitness. The allele frequency of these four variations would be the most common variation.
Surviving Adaptations - Post Disaster
Adapted Hawaiian Green Sea Turtle
Chelonia mydas, or more commonly known as the green sea turtle, is distributed throughout the world's tropical and subtropical oceans. Two
sub - populations of green sea turtles exist in the Atlantic and the eastern Pacific ocean. More specifically, adult green sea turtles mostly dwell in coral reefs, lagoons, mangroves, and seagrass beds. They prefer fairly shallow waters in such areas.

Breeding grounds of the sea turtle are the natal beaches of the female population; natal beaches are where an individual was born. For the purpose of this presentation, the focused population of the green sea turtle will be those of the Hawaiian Islands. Interestingly, this population is fond of basking in the sun on the shores of the Northwestern Hawaiian Islands, an infrequent behavior among seafaring turtles.
. Digital image.
See Turtles
. Web. 5 Mar. 2014.
5292016 F520
. Digital image. Web. 5 Mar. 2014.
800pxmtcleveland Iss013e24184
. Digital image.
. Web. 5 Mar. 2014.
. Digital image.
SparkNotes: Today's Most Popular Study Guides
. Web. 5 Mar. 2014.
FFS Sea Turtles 440
. Digital image.
. Web. 5 Mar. 2014.
Green Sea Turtle
. Digital image.
Peter Liu
. Web. 5 Mar. 2014.
Green Sea Turtle
. Digital image.
Sea Turtles
. Web. 5 Mar. 2014.
Green Sea Turtle Hawaii
. Digital image.
National Geographic
. Web. 5 Mar. 2014.
Green Seagrass Rpvandam
. Digital image.
. Web. 5 Mar. 2014.
Green Turtle
. Digital image. Web. 5 Mar. 2014.
Marchenko, Dmitry.
Green Sea Turtle, Red Sea
. Digital image.
National Geographic
21 Sept. 2012. Web. 5 Mar. 2014.
Pirate Fishermen Hook Endangered Green Sea Turtle Conservationists Rescue It 2
Digital image. Web. 5 Mar. 2014.
Sea Turtle Underwater
. Digital image.
Desktop Wallpaper Wallpapers Downloads Free
. Web. 5 Mar. 2014.
Sea Turtle Wallpaper
. Digital image.
Sea Turtle Wallpaper - WallpaperTube
. Web. 5 Mar.
Works Cited
Green Sea Turtles
. Web. 5 Mar. 2014.
Boumis, Robert. "Symbiosis of Sea Turtles & Yellow Tang."
. Demand Media. Web.
5 Mar. 2014.
"Effects on the Environment."
University of St. Francis - Joliet, II
Http://www.stfrancis.edu/content/ns/bromer/earthsci/student9/Web%20PageMichAmand/Michelle.htm. Web. 5 Mar. 2014.
"Green Sea Turtle (Chelonia Mydas)."
Fish and Wildlife Service
. Web. 5 Mar. 2014.
"Green Sea Turtle."
National Geographic
. Web. 5 Mar. 2014.
"The Hawaiian Green Turtle (Chelonia Mydas)."
The Hawaiian Green Turtle
. 24 Jan. 2004.
Web. 5 Mar. 2014.
"How Do Volcanoes Affect Plants and Animals? | Volcano World."
How Do Volcanoes Affect
Plants and Animals? | Volcano World
. Web. 5 Mar. 2014.
"Information About Sea Turtles: General Behavior."
Sea Turtle Conservancy
. Web. 5 Mar.
"Ocean Life: Green Sea Turtle - Characteristics."
. Web. 5 Mar. 2014.
"Sea Turtle Photos - Office of Protected Resources - NOAA Fisheries."
Sea Turtle Photos -
Office of Protected Resources - NOAA Fisheries
. Web. 5 Mar. 2014.
"What Sea Turtles Eat."
What Sea Turtles Eat
. Web. 5 Mar. 2014.
Works Cited
Video - Hawaiian Green Sea Turtle Grazing
Video - Hawaiian Volcanic Eruption
Green sea turtles basking on the beach of the French Frigate Shoals in the Northwestern Hawaiian Islands
A Hawaiian green sea turtle in shallow waters near a shoreline
An adult green sea turtle grazing on seagrass

A green sea turtle receiving a cleaning
By Caitlin Lambie & Matthew Nguyen
Wednesday, March 5th, 2014 - 03/05/14
6th Period / Pre - AP Biology / Mrs. Cooley

A more solid, darker brown carapace in contrast to a mottled, lighter brown carapace
A contrast between two green sea turtles and their beaks; the top beak is sharper while the bottom beak is rounder
The explosion of a volcano and the smoke it expels; notice the polluted water to the north of the volcano
Petrified, rugged terrain
Directional Selection
Light Shell
Sharp Beak
Dark Shell
Round Beak
Darkened Shell
Round Beak
Increased Clutch Quantity
Adult Female
Edited digital image using Adobe Photoshop CS6
(Burned and Smudged)
The End
Full transcript