Why multipartite viruses infect plants rather than animals

Being in between living and non-living, viruses are, in general, strange. Among viruses, multipartite viruses are among the most peculiar — their genome is not packed into one, but many, particles. Multipartite viruses primarily infect plants rather than animals. A recent article uses mathematical and computational models to explain this observation.

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250-million-year-old evolutionary remnants seen in muscles of human embryos

A team of evolutionary biologists have demonstrated that some limb muscles known to be present in many mammals but absent in the adult human are actually formed during early human development and then lost prior to birth. These findings offer insight into how our arms and legs evolved from our mammalian ancestors, and also help explain rare limb anomalies found in humans born with congenital malformations.

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The hidden ark: How a grassroots initiative can help save fish from extinction

Freshwater fish are the most threatened vertebrate group, and species are disappearing faster than scientists can describe them. A new study shows that aquarium hobbyists can play an important role in freshwater fish conservation by filling in the gaps left by the scientific community and conservation organizations.

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Climate change could pit species against one another as they shift ranges

Species have few good options when it comes to surviving climate change — they can genetically adapt to new conditions, shift their ranges, or both. But new research indicates that conflicts between species as they adapt and shift ranges could lead experts to underestimate extinctions, and underscores the importance of landscape connectivity.

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What did ancient crocodiles eat? Study says as much as a snout can grab

To study the diet of ancient crocodiles, two researchers combined mathematical analyses of the animals' shapes, surveys of modern crocodiles' diet, modeling methods for reconstructing the diet of fossil groups, and forensic-style interpretations of damaged bones from the distant past.

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Collapse of desert bird populations likely due to heat stress from climate change

Last year, biologists discovered that bird populations in the Mojave Desert had crashed over the past 100 years. The biologists now have evidence that heat stress is a key cause. Simulations with a computerized 'virtual bird' suggest that with higher temperatures, birds need more water to keep cool. Larger insectivores or carnivores should be most affected, and small seed-eaters less so if drinking water is available: just as the biologists reported last year.

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A closer look at monogamy and polygamy in brood parasitic birds

Researchers have discovered that cowbirds conform to Bateman's Principle, despite investing no energy into parental care. Surprisingly, 75% of the cowbirds in the system were monogamous. Future research will expand upon these findings and broaden the understanding of how cowbirds might select the nests they parasitize, what role the males could play to assist the females, and why monogamy could be such a benefit.

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