根据发表在《科学》期刊上的一项研究，美国地质调查局 Powell Center Status of Butterflies of the United States Working Group 报告，美国的蝴蝶数量从 2000 年到 2020 年减少了 22%。研究人员称，美国每个地区和几乎所有蝴蝶物种的数量都在下降。在研究的 342 种蝴蝶中，近三分之一数量下降一半以上，22 种下降了九成以上，只有 9 种数量有所增加。其中广泛分布于美国西部的 West Coast lady 数量下降了八成。导致蝴蝶数量下降的可能因素包括：栖息地丧失、杀虫剂、气温升高和地面干燥。其中杀虫剂被认为是最主要因素。
Theconversation:Butterflies declined by 22% in just 2 decades across the US – there are ways you can help save them
根据发表在《科学》期刊上的一项研究，美国地质调查局 Powell Center Status of Butterflies of the United States Working Group 报告，美国的蝴蝶数量从 2000 年到 2020 年减少了 22%。研究人员称，美国每个地区和几乎所有蝴蝶物种的数量都在下降。在研究的 342 种蝴蝶中，近三分之一数量下降一半以上，22 种下降了九成以上，只有 9 种数量有所增加。其中广泛分布于美国西部的 West Coast lady 数量下降了八成。导致蝴蝶数量下降的可能因素包括：栖息地丧失、杀虫剂、气温升高和地面干燥。其中杀虫剂被认为是最主要因素。
Theconversation:Butterflies declined by 22% in just 2 decades across the US – there are ways you can help save them
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BY Solidot
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How to Invest in Bitcoin?
Like a stock, you can buy and hold Bitcoin as an investment. You can even now do so in special retirement accounts called Bitcoin IRAs. No matter where you choose to hold your Bitcoin, people’s philosophies on how to invest it vary: Some buy and hold long term, some buy and aim to sell after a price rally, and others bet on its price decreasing. Bitcoin’s price over time has experienced big price swings, going as low as $5,165 and as high as $28,990 in 2020 alone. “I think in some places, people might be using Bitcoin to pay for things, but the truth is that it’s an asset that looks like it’s going to be increasing in value relatively quickly for some time,” Marquez says. “So why would you sell something that’s going to be worth so much more next year than it is today? The majority of people that hold it are long-term investors.”
