Vertebrates developed about 550 million years ago. The oldest vertebrate fossils are those of FISH with no jaws. These e<span>arly jawless fish did not have paired fins and their bodies were covered with heavy, bony scaled, but their skeletons were made of cartilage. For the next 50 million years, they were the only vertebrates.</span>
Answer:
I think it is
Natural disasters are a concern for human, life and property, but there is nothing we can do to predict them or prepare for them
The answer to this question is letter C. <span>The organism evolved during identification.
</span>A scientist has correctly gone through all the possible steps in a dichotomous key, but has not identified an insect. He was not able to identify the insect because t<span>he organism evolved during identification.
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Choices to this question are:
A) The scientist must have made a mistake.
B) The insect might be an unknown variation or a new species.
C) The organism evolved during identification.
D) The dichotomous key had to many questions.