在现代生态系统中，雀形目鸟类（Passeriformes）被认为是黄蜂拟态的主要选择者。然而，在早渐新世的欧洲，雀形目鸟类却非常罕见。那么，在那个时期，是什么因素促使了这种高度精准的拟态形成呢？研究人员推测，选择最早已知的高度精准黄蜂拟态者的可能是 Coraciimorphae 和 Apodiformes ...

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Warner Bros. Discovery Inc. Series A $10.37-0.64-5.81% ...

Safe-haven gold hit a fresh record high on Friday as an index of global shares fell, weighed down by worries over a looming trade war sparked by tariff decisions from U.S. President Donald Trump.

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Magnificent Seven represent 32% of the S&P 500 as of March 2025, up from 12.3% in 2015. From 2015 to 2024, these seven companies achieved a 697.6% return, outperforming the S&P 500. In 2025, the ...

There are a lot of different numbers cited for the average annual return of the index. And while the average return is easy to compute, it’s important to define what you’re computing. The ...

In addition to prey, many natural enemies (predators and parasitoids) need sources of pollen and nectar. These sources are especially important for parasitoid wasps as well as the adult stages of ...