It’s almost April, which means that people around the country are pulling out their checkbooks and giving money to the government, or finding ways to avoid doing so. (And by “people,” we mean “corporations” — same difference, right?) Unsurprisingly, some groups are better at tax avoidance than others. More surprisingly, perhaps, is who does the most skillful job at finding ways around paying taxes. Firms with Republican CEOs “show a significantly higher level of tax avoidance than do companies with CEOs of no obvious political preference,” according to new research co-authored by Johns Hopkins business professor Xian Sun.

In a time of crunching budgets and shaky economies, every tax dollar counts. The money that these firms squirrel away through tax-avoidance strategies “can be viewed as revenue that isn’t realized by the government for public benefit,” said Sun.

How exactly does one avoid taxes on a massive scale, you may be wondering. “The firms with Republican CEOs used avoidance measures that ranged from aggressive to less aggressive, including measures that involved long-term tax avoidance,” Sun said. “At the companies with Democratic CEOs, the avoidance methods generally involved book-to-tax difference and shelter activities. These are aggressive measures but don’t figure in the firm’s overall level of tax avoidance or in its long-term avoidance strategy. For these executives, improving the bottom line, rather than politics, appeared to be their primary motivation for any tax avoidance.” The study determined political affiliation by looking at CEOs’ donations to the two major parties; about 60 percent gave to Republicans.

Sometimes it’s cloudy, sometimes it’s clear — and thus it has been for the past 2.5 billion years or so, according to new research co-authored by scientists at the University of Maryland. Well, “cloudy” isn’t exactly the best way of describing what the sky might’ve looked like long ago, in the days before Earth oxygenized and became home to complex life. It was more like an orange haze full of hydrocarbon particles, something of an “anti-greenhouse effect,” according to UM geochemist Jams Farquhar. The haze warmed the Earth’s atmosphere, but didn’t do so continuously. Instead, there were also periods of clear, sunny, hydro-carbon free skies.

“What most surprised us about these findings is that it seems to indicate the atmospheric events were discrete in nature, flip-flopping between one stable state into another,” Farquhar said. “This type of response is not all that different from the way scientists think climate operates today, and reminds us how delicate the balance between states can be.”