The volcanic islands known as the Galapagos Islands are found 600 miles off the coast of Ecuador and are home to the Galapagos penguins, the only species of penguins in the world to live north of the equator. Despite the common belief that penguins only live in the Arctic, the Galapagos Islands have temperatures that vary from 70-90° Fahrenheit over the course of the year. The distribution of these birds in their environment correlates with the “Cromwell Current, which provides cold nutrient-rich surface water,” meaning that the penguins follow the cool water patterns (Davis).
The penguins feed on small fish like sardines and mullet, and their predators include sharks, sea lions, hawks, and crabs. The Galapagos penguins have been adapting for the last 60 million years and developing their derived characteristics from their ancestors. Galapagos penguins belong to the domain of Eukarya, just like all other life, except for bacteria, and they belong to the animal kingdom.
The penguins “sleep with their flippers [turned] outward … to prevent … eat from escaping their bodies” during the chilly nights (Galapagos Penguins Penguin-World). They also hold their flippers on their feet as they walk “to prevent the sunlight from burning their sensitive feet” (Galapagos Penguins Penguins-World). The Galapagos penguins are one of the smallest species of penguins, weighing in at about 5. 5 pounds and only being about 20 inches tall, and they rely heavily on vocal calls for communication and mating. They live in burrows and are very social for protection from predators.
The Galapagos penguins are classified as an endangered species due to El Nino and El Nina causing food supplies to drastically change each year, as well as human disturbance to their environment, such as the use of fishing nets and pollution (Galapagos Penguins EO Earth). The taxon genus of the Galapagos Penguins is Spheniscus and the taxon species is mendiculus, making the name assigned by Linnaeus’ two-part naming system called binomial nomenclature Spheniscus mendiculus.
The Spheniscus mendiculus’s derived characteristics include their waterproof feathers interweaved with muscles, their black and white coloring, and their ability to survive in warm climates. In the taxon order of flightless birds called Sphenisciformes, the derived characteristic is waterproof feathers with muscles interweaved into them. This order immerged about 65-60 million years ago.
According to the Science Dictionary, Sphenisciformes are birds where the “flight feathers are lacking; the wings are stiff and used as paddles in swimming; th e feet are webbed; the bones are solid and there are no air sacs” leaving these birds unable to fly and very steady swimmers. The ability to swim is a derived characteristic of all Spheniscidae from other birds, as they live in coastal areas and use “submarine flight” to catch their prey that live in the water (Hickman).
The birds’ waterproof feathers were passed from generation to generation because the birds with the feathers that were waterproof were able to catch prey, and those that caught prey survived and passed their traits on to their offspring. As well as waterproof feathers, the family of Spheniscidae has very distinct coloring which can be proved by a cladogram that sets them apart from other families of birds. Birds’ evolutionary relationships first started back with a species taxon of dinosaurs called theropods.
Because of cladistic research, it has been proven that “birds evolved directly from dinosaurs” (Miller). By looking at the bone structure and the feathers, professors of phylogeny “reason that theropods [are] the ancestors of birds” and they lived about 150 million years ago (The origin of birds). During the Cretaceous Period, about 115 years ago, there was a change in the structure of the birds leading to wings and flight for some birds. In the picture to the right, a cladistic diagram is shown to show the relationship between the theropods and birds.
Today, the taxon of family includes many hundreds of families of birds, and one of the derived characteristics of all Spheniscidae is their black and white coats. Spheniscidae are typically black with white stomachs. Their coloring is useful as camouflage because the white makes them difficult to see from under the water and the black makes them difficult to see from above as they are swimming. This evolutionary relationship occurred because those that survived because of their coloring passed it on to their offspring due to natural selection.
The Spheniscus mendiculus also have adapted to survive in a warm climate. The taxons that classify the Spheniscus mendiculus allows them to have developed a derived characteristic to be able to survive in an area where the average temperatures are 70-90° Fahrenheit, which is unusual because penguins typically live in Antarctic areas. The molecular clock indicates that about “4 million years ago … a small population … successfully arrived in the islands and established a colony” (Galapagos).
The Spheniscus mendiculus can survive there based on the cold water currents called the Peruvian Coastal Current and the Cromwell countercurrent. These currents bring cold water to the area, allowing the Spheniscus mendiculus to survive there. In recent years, they have adapted to be smaller because smaller animals are more efficient in radiating heat. Because the Spheniscus mendiculus have derived these characteristics, they are the best suited to live in their environment.
The Spheniscus mendiculus evolved from dinosaurs called theropods, which is proved by cladistic analysis from scientists. They are members of the Spheniscus genus and the mendiculus species. Because they have waterproof feathers, they can capture their prey. Because they are black and white, they are camouflaged to their environment, and therefore are protected from predators. Because they are smaller and have learned to work with the ocean currents, they can survive in a warm climate.