If evolution happens gradually as genetic changes are passed from one generation to the next, you’d expect the fossil record to show the transitional forms along the way. But it doesn’t always do that. In some cases, the fossil record clearly shows a pattern of gradual change from ancestor to descendent. But more often, it seems to show jumps from one species to another with no transitional forms in between. “It's quite rare to actually have examples in the fossil record where something ...read more

Strange as it may seem, early germ theorists could tell us a lot about today’s attitudes toward climate change.While researching for a new book about the history of emerging infections, I found many similarities between early debates over the existence of microbes and current debates over the existence of global warming.Both controversies reveal the struggles of perceiving an unseen threat. Both reveal the influence of economic interests that benefit from the status quo. But most importantly, ...read more

As La Niña continues to stir in the tropical Pacific Ocean, the latest analysis shows there’s a 70 percent chance it will develop between August­ and October.The climate phenomenon shifts the world's atmospheric circulation, changing weather patterns around the globe. Characterized by cooler-than-average sea surface waters in large swaths of the tropical Pacific, it also usually takes the edge off human-caused heating of the planet, albeit temporarily.But even taking that likely cooling eff ...read more

One of the most frequent questions astronauts get asked is, how do you go to the bathroom in space? For decades, their reply has been the same icky answer: they essentially soil their suits. Astronauts in transit (space stations have more sanitary solutions — but even those can sometimes go awry) have long depended on what are essentially adult diapers to absorb their urine. For short missions, this is merely uncomfortable, and just a bit gross. But for longer journeys — like, perhaps ones p ...read more

The percentage of Americans seeking mental health treatment nearly doubled between 2004 and 2022, with almost a quarter of the population reporting that they saw a mental health care professional in 2022.This surge in help-seeking has many potential explanations. The pandemic, along with other external stressors, led to unprecedented high rates of anxiety and depression across all age groups.Yet the majority of Americans with a mental health condition are not receiving adequate treatment or any ...read more

When you first encounter a hummingbird moth, you might mistake it for a tiny hummingbird flitting from flower to flower. However, these flying insects are simply displaying their mastery of mimicry. Often referred to as hawk moths or sphinx moths, hummingbird moths are captivating critters with fascinating behaviors and appearances, which makes them a favorite of nature enthusiasts and backyard gardeners alike. In this article, we'll explore the world of the hummingbird moth, discussing what mak ...read more

There’s more to beach sand than meets the eye. It has stories to tell about the land, and an epic journey to the sea. That’s because mountains end their lives as sand on beaches.Over time, mountains erode. The mud, sand, gravel, cobbles and boulders they shed are washed into streams, which come together to form rivers. As they flow down to the sea, all this sediment is ground up and worn down in nature’s version of a rock tumbler.Big rocks break down into smaller pieces, so most of what re ...read more

A researcher working alone – apart from the world and the rest of the wider scientific community – is a classic yet misguided image. Research is, in reality, built on continuous exchange within the scientific community: First you understand the work of others, and then you share your findings.Reading and writing articles published in academic journals and presented at conferences is a central part of being a researcher. When researchers write a scholarly article, they must cite the work of p ...read more

Dingoes and dogs look similar — until you compare their genomes. A study in PNAS examines this seemingly counter-intuitive outcome and explains the genetic divergence between the two species.“The genetic difference might seem counter-intuitive because dingoes and domestic dogs share a common ancestor,” says Sally Wasef, a geneticist from Queensland University of Technology and a co-author of the paper. “However, the key factor is the period of isolation. Dingoes have been isolated from o ...read more

DNA extracted from a woolly mammoth excavated in 2018 was so well preserved that scientists have, for the first time, constructed a three-dimensional genome from ancient genetic material. That information, from an animal that died in Siberia about 52,000 years ago, allows better comparisons between extinct mammoths and contemporary elephants, according to a report in Cell.Freeze-Dried Woolly MammothA team of 56 scientists from four organizations collaborated to find the fossil, excavate it, then ...read more