In 2004, Jun-Yuan Chen and David Bottjer found a fossil approximately 580-600 million years old. Why was this particular fossil significant?
A. It was one of the earliest fossils of a single-celled organism.
B. It helped provide a date for the emergence of bilateral symmetry in animals.
C. It provided evidence that the earliest life forms were heterotrophic.
D. It provided evidence that the earliest life forms were autotrophic.
E. It helped provide a date for the emergence of vertebrates.
Answer: B
You might also like to view...
Species - as opposed to individuals or populations - are considered the ultimate evolutionary unit because (select all correct choices)
A. new mutations can potentially spread within a species, but not beyond it. B. species can become extinct. C. species give rise to other species. D. changes in gene frequencies over time can only be observed within species, not within populations. E. none of these
How do bony fish regulate buoyancy?
A. With a protective operculum B. By constantly swimming at an upwards angle C. Through the calcium in the bones, which makes the skeleton lighter than the water D. With an air-filled swim bladder
Which of the following is an advantage of sexual reproduction?
a. Sexual reproduction is faster than asexual reproduction. b. Individual organisms do not have to seek mates. c. Sexual reproduction promotes genetic variation. d. Sexual reproduction is more energy efficient. e. Individual organisms are protected from harmful mutations.
The earliest vertebrates had jaws
____________________ Indicate whether the statement is true or false.