Sixty-five million years ago, the last of the non-avian dinosaurs went extinct. So too did the giant mosasaurs and plesiosaurs in the seas and the pterosaurs in the skies. Plankton, the base of the ocean food chain, took a hard hit. Many families of brachiopods and sea sponges disappeared. The remaining hard-shelled ammonites vanished. Shark diversity shriveled. Most vegetation withered. In all, more than half of the world's species were obliterated. Why Dinosaurs Disappeared The cause of the mass extinction that marks the end of the Cretaceous and the beginning of the Paleogene is a scientific mystery. The extinction wiped out the dinosaurs while most mammals, turtles, crocodiles, salamanders, and frogs survived. Birds escaped. So did snails, bivalves, sea stars (starfish), and sea urchins. Even hardy plants able to weather climate extremes fared okay. Scientists tend to huddle around one of two hypotheses that may explain the Cretaceous extinction: an extra...
Assalamualaikum Wr. Wb First of all, lets pray and thanks unto our god Allah who has been giving us some mercies and blessings so we can attend and gather in this place in good condition and happy situation. Brother and sister, I would like to deliver my speech today. My theme today is about the "teachers ' day" which falls squarely on 25 November. On this day we all convey a profuse gratitude to Mr. and Mrs. Teacher who had devoted as the educators. Thanks to the devotion of Mr. and Mrs. Teacher who has poured out upon us, so we can achieve a good result. With the guidance of Mr. and Mrs. Teacher, we feel it is under the supervision and care of the elderly siblings alone. This is because the teachers have formed a close bond. I represent from friends saying "happy teachers ' day" On the other hand, it is also called the teaching profession as a noble profession. In this regard, it should be realized that a teacher in the exercise of ...
Terimah kasih guru Kaulah pembimbingku…… Kaulah pengajarku…… Kaulah pendidikku…… Guru…… Itulah julukanmu…… Yang tak pernah bosan dalam…… Mengajar dan membimbingku Guru…… Tanpa dirimu aku akan hancur…… Tanpa dirimu aku akan sengsara…… Tanpa dirimu aku akan sesat…… Guru…… Terima kasih…… Atas segala jasa-jasamu……
Komentar
Posting Komentar