The discovery of well-preserved pelves and a partial pelvic fin from Tiktaalik roseae, a 375 million-year-old transitional species between fish and the first legged animals, reveals that
the evolution of hind legs actually began as enhanced hind fins
.
Why is the Tiktaalik roseae important?
Zerina Johanson, a vertebrate palaeontologist at the Natural History Museum in London, said: “Tiktaalik is
one of the most important fish fossils for unravelling the evolutionary transition from fish living in water to tetrapods living on land
.
Why is Tiktaalik important to the study of evolution?
Tiktaalik lived about 12 million years before the first tetrapods (which are approximately 363 million years old). So, the existence of tetrapod features in a fish like Tiktaalik is significant because it
marks the earliest appearance of these novel features in the fossil record
.
Why is Tiktaalik such an important transitional fossil?
So why is Tiktaalik referred to as a transitional creature? Its mix of characteristics of fish and of tetrapods suggest that
it represents one of the moments in the transition between fish and tetrapods
. them have found fossils.
What evidence does the discovery of Tiktaalik give to support the theory of evolution?
What evidence does the discovery of Tiktaalik give to support the theory of evolution? Tiktaalik shows
that extinct species are related to modern species, which supports the idea of common ancestry
. Tiktaalik shows that fish decided to grow legs at some point, which allowed them to walk on land.
Are humans from Tiktaalik?
The Human Edge: Finding Our Inner Fish One very important human ancestor was an ancient fish. Though it lived 375 million years ago, this fish called Tiktaalik had
shoulders, elbows, legs
, wrists, a neck and many other basic parts that eventually became part of us.
Is Tiktaalik extinct?
Tiktaalik roseae, an
extinct fishlike aquatic
animal that lived about 380–385 million years ago (during the earliest late Devonian Period) and was a very close relative of the direct ancestors of tetrapods (four-legged land vertebrates).
What characteristics of Tiktaalik are tetrapod like?
Tiktaalik retained both fish and tetrapod characteristics. Its fish characteristics include
scales, fins, and gills
, and its tetrapod characteristics include a neck, ribs capable of bearing weight, a flat head, dorsally positioned eyes, a fin skeleton, and ear notches (The University of Chicago, 2006).
Why is Tiktaalik called a Fishapod?
The name Tiktaalik is an Inuktitut word meaning ” burbot”, a shallow-water fish. The “fishapod” genus received this name
after a suggestion by Inuit elders of Canada's Nunavut Territory, where the fossil was discovered
.
What are the characteristics of Tiktaalik that make it a transitional form?
Tiktaalik, for example, had
fins with thin ray bones, scales, and gills
like most fish. However, it also had the sturdy wrist bones, neck, shoulders, and thick ribs of a four-legged vertebrate. Tiktaalik was specialized for life in shallow water, propping itself up on the bottom and snapping up prey.
What is an example of a transitional fossil?
Basilosaurids and Ambulocetus
, among others, are transitional fossils that show a progression of animals who transitioned from terrestrial to sea life. Finally, dinosaur-like fossils such as Archaeopteryx and Confuciusornis appear to have been able to fly, and are transitional fossils to modern day birds.
How do scientists know that Tiktaalik is a transitional fossil?
To find a transitional fossil between land animals and fish, we start by
looking at the very first tetrapods to show up in the fossil record
. Then, we look for fish which had a similar pattern of bones in their fins as the tetrapods had in their limbs.
What characteristics of Tiktaalik solidify it as a transition fossil?
Paleontologists have uncovered new fossils from Tiktaalik roseae, which, while still a fish, is considered a transitional fossil that also has traits common to the first four-footed animals. This more complete picture of Tiktaalik suggests that the
creature had strong, mobile hind fins
.
How do you explain natural selection?
Natural selection is the
process through which populations of living organisms adapt and change
. Individuals in a population are naturally variable, meaning that they are all different in some ways. This variation means that some individuals have traits better suited to the environment than others.
What important step in evolution did the Tiktaalik fossil demonstrate?
The discovery of well-preserved pelves and a partial pelvic fin from Tiktaalik roseae, a 375 million-year-old transitional species between fish and the first legged animals, reveals that
the evolution of hind legs actually began as enhanced hind fins
.
Who discovered Tiktaalik fossil?
Discovered in 2004 by
Prof Shubin, Dr Edward Daeschler of Drexel University, and the late Dr Farish A. Jenkins, Jr., of Harvard University
, Tiktaalik roseae is the best-known transitional species between fish and land-dwelling tetrapods. Tiktaalik roseae lived in Devonian period around 375 million years ago.
