21. Nor does the hypothesis that infantile amnesia reflects repression- or holding back- of sexually charged episodes explain the phenomenon.
22. Maturation of the frontal lobes of the brain continues throughout early childhood, and this part of the brain may be critical for remembering particular episodes in ways that can be retrieved later.
23. Consistent with this view parents and children increasingly engage in discussions of past events when children are about three years old.
24. The better able the person is to reconstruct the perspective from which the material was encoded, the more likely that recall will be successful.
25. The world looks very different to a person whose head is only two or three feet above the ground than to one whose head is five or six feet above it, 0lder children and adults often try to retrieve the names of things they saw, but infants would not have encoded the information verbally．
26. Conversely，improved encoding of what they hear may help them better understand and remember stories and thus make the stories more useful for remembering future events.
27. Missing until recently were fossils clearly intermediate, or transitional, between land mammals and cetaceans.
28. Pakicetus was found embedded in rocks formed from river deposits that were 52 million years old.
29. The skull is cetacean-like but its jawbones lack the enlarged space that is filled with fat or oil and used for receiving underwater sound in modern whales.
30. Several skeletons of another early whale, Basilosaurus, were found in sediments left by the Tethys Sea and now exposed in the Sahara desert.
