Scientists have long believed that bees existed up to some 200 million years ago. This notion has recently come under some speculation because of a lack of any significant evidence to support this theory. Key missing evidence includes fossil records, the lack of flowering plants to support bee life, and recently revealed discrepancies in the fossil record.
To date, the oldest known bee discovered is a 100 million-year-old specimen preserved in amber. This ancient specimen, trapped in tree resin, is at least 35-45 million years older than any other known bee fossil. What is concerning scientists is the lack of any fossil evidence older than 100 million years. Fossil records for other plant, animal and insect species are quite complete, however, the bee is missing a similarly lengthy record.
The ancient world lacked flowering plants. This is important because bees are pollen-dependent and rely on flower pollen and nectar for energy, protein and other nutrients. Flora in the ancient world 200 million years ago were mostly dominated by conifers which did not flower or produce the pollen and nectar necessary for bee survival. Lacking this food source, it is highly skeptical that bees could have existed 200 million years ago.
Several of the fossil records being studied by scientists have also brought to light major discrepancies that exist between modern beehives and beehives of the ancient world. Specifically, ancient beehives seem to have a different organization and structure compared to that of modern beehives. This variance in evidence in the fossil record has led experts to speculate that these fossils are not fossils of beehives, but rather nests of another insect species.
听力音频：
Summarize the points made in the lecture you just heard, explaining how they cast doubt on the specific theories discussed in the reading passage.
When people are asked about the most important discoveries or inventions made in the last two hundred years, they usually mention something very obvious, like the computer or the cell phone. But there are thousands of other discoveries or inventions that have had a huge impact on how we live today. What scientific discovery or technological
invention from the last two hundred years—other than computers and cell phones— would you choose as being important? Why?
Paul的观点：
I mean, we’re so used to science and technology that we are not even aware of all the things we use in our daily lives. I would probably choose space satellites. This technology happened in the last hundred years, and it has become important for so many things. Just think about navigation, or telecommunications, or even the military.
Claire的观点：
I am thinking about medical progress. Like, for example, when scientists discovered things about healthy nutrition. I am thinking of identifying all the vitamins we need to stay healthy. I am not sure exactly when the vitamin discoveries happened, but I know they are very important. Our health is much better than it was 200 years ago.
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