D) The Earth was hit by a one or more objects from space 65 million years ago. The iridium layer shows an extraterrestrial cause for the extinction at the Cretaceous Tertiary boundary, discovered by the Alvarez family. The first discovery of this layer was in the Bavarian alps, in Lattengebirge. The Alverez family proposed that the extinction of the dinosaurs was due to a large meteor hitting the Earth at the end of the Cretaceous period, marking the KT boundary with this clay layer which has a high content of iridium. Iridium is not common on Earth, but is common in meteors.
Answer: dinosaurs and birds
Plentiful collection of f<span>ossils of early birds and their most immediate predecessors has settled the century-old controversy about the origin of birds. Birds are now safely declared to evolve from a group of dinosaurs known as maniraptoran theropods. Birds have similar shape of the bones as a variety of maniraptorans have. A host of fossils have shown also that the maniraptorans lay looked alike eggs as that of birds and they resemble the birds in the way they laid their eggs also. Those reasons prove that they are most closely related.</span><span>
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<u>ANSWER:</u>
The correct order is- Zygote, Blastula, Gastrula, Fetus.
<u>EXPLANATION:</u>
- The embryo develops from the zygote which is formed when the gametes fuse in the process of "fertilization".
- The zygote undergoes cell division to form blastula which is a "ball of cells".
- Gastrula leads to the rearrangement of cells of the blastula into three layers that differentiate into different systems of organ.
- The last stage is the fetus which then develops into a baby.
An equator, is the definition of that!
Answer:
The best example of hypothesis which leads to new experiment methods was done by Morgan where he used fruit flies.
