There are all sorts of ways to reconstruct the history of life on Earth. Pinning down when specific events occurred is often tricky, though. For this, biologists depend mainly on dating the rocks in which fossils are found, and by looking at the “molecular clocks” in the DNA of living organisms.
There are problems with each of these methods. The fossil record is like a movie with most of the frames cut out. Because it is so incomplete, it can be difficult to establish exactly when particular evolutionary changes happened.
Modern genetics allows scientists to measure how different species are from each other at a molecular level, and thus to estimate how much time has passed since a single lineage split into different species. Confounding factors rack up for species that are very distantly related, making the earlier dates more uncertain.
These difficulties mean that the dates in the timeline should be taken as approximate. As a general rule, they become more uncertain the further back along the geological timescale we look. Dates that are very uncertain are marked with a question mark.
Answer:
The skull is from a fossil skull of Styracosaurus - a horned dinosaur.
Explanation:
This skull image is the skull of a Styracosaurus dinosaur who was a huge dinosaur almost 5 meters or more with the horned present on the skull. This is a fossil skull representation from the fossils.
Styracosaurus was present 75 million years ago during the Cretaceous period who was a completely herbivorous ceratopsian dinosaur.
Thus, the skull is from a fossil skull of Styracosaurus - a horned dinosaur.
James Dewey Watson is an American molecular biologist, geneticist and zoologist. In 1953, he co-authored with Francis Crick the academic paper proposing the double helix structure of the DNA molecule. Watson, Crick, and Maurice Wilkins were awarded the 1962 Nobel Prize in Physiology or Medicine "for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material". Watson earned degrees at the University of Chicago and Indiana
That instant ... typically some moment on june 21 or 22 ... marks
the beginning of the northern hemisphere Summer.
Kinetic chain checkpoints represents the six anatomical locations of predictable movement patterns and is denoted as option B
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What is Kinetic chain checkpoints?</h3>
These are groups of body segments, connecting joints, etc which have a connection to the spine in the human body.
They work together to ensure body parts are easily moved and makes the detection of movement dysfunctions easier.
Read more about Kinetic chain checkpoints here brainly.com/question/789840
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