The extinction of the dinosaurs

Since their discovery, at the beginning of the 19th century, dinosaurs have always awakened human imagination. The past existence of such large animals, which seemed to have left no trace in the current fauna, is quite suggestive. In the multitudinous field of science, dinosaurs have always occupied an extremely attractive place. Dinosaurs have appeal.

On the other hand, the mystery of the disappearance of dinosaurs was soon posited. What could have caused their extinction? In the next century and a half, various possible causes were proposed, such as the following:

• It was said, for example, that primitive mammals could have caused the extinction of dinosaurs by eating their eggs. The trouble is, both groups of animals lived together for a hundred million years without any problem. In fact, mammals were cornered by their giant neighbors and could not develop and spread until they disappeared.
• It was also said that the apparition of flowering plants (Angiosperms) during the Cretaceous period, the last when dinosaurs lived, could have caused their extinction by a change in their diet. The trouble is, the Cretaceous period was very long, and flowering plants appeared thirty million years before the extinction of the dinosaurs. If they could put up with that diet for so long, why should it suddenly be fatal for them?
• Another reason adduced was a change of climate. During the Mesozoic Era (the age of the dinosaurs) the Earth's climate was quite warm. Then, in the Tertiary period, it was colder. The bad news is that climate changes are usually gradual, while the disappearance of dinosaurs does seem to have been quite fast. Therefore it was proposed that the cause of the extinction could have been a sudden catastrophe that would have caused a sudden climate change.

The star of Bethlehem

Giotto - Adoration of the Magi

Chapter 2 of St. Matthew’s Gospel begins with these words:

After Jesus was born in Bethlehem in Judea, during the time of King Herod, Magi from the east came to Jerusalem and asked, “Where is the one who has been born king of the Jews? We saw his star when it rose and have come to worship him.”

First, a few considerations about this text:

• Magi is a term with different meanings. Strictly speaking, it was applied to the priests of Mazdayasna, the religion of Zoroaster. Zoroastrian magi were frequently devoted to astrology (the name then given to the science we now call astronomy). So, in a broad sense, the word magi could be applied to anyone who worked in that science. The New Testament does not say that they were kings. That is a later tradition.
• It will be noted that the text does not say that they were three. They must be at least two, since the term is plural, but later thinkers have discussed whether they were two, three, or even six. The three magi is also a later tradition.
• It is explicitly stated that King Herod was alive. When did Herod die? Since Emil Schürer (1896) it has been assumed that he died in the year 750 ab Urbe condita (a.U.c., since the founding of Rome), which corresponds to year 4 b.C.e. (before the Christian era). From this, many historians deduced that Jesus Christ must have been born before that date. Therefore Dionysius Exiguus, author of the idea of ​​numbering the years since the birth of Christ, would have made a mistake in assigning the year 754 a.U.c. to his birth. But some modern historians think that Herod could have died in the year 753 a.U.c. (year 1 b.C.e.), and that his sons pushed back the beginning of their own reign, thus causing the discrepancy and leading Emil Schürer to a wrong conclusion. Consequently, the most probable date for the birth of Christ would be between the year 7 b.C.e. and the year 2 b.C.e.