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Gophers are kinda famous for their knack for destroying farms and gardens by digging entrance holes to their tunnels and pushing up mounds of dirt as they burrow below ground. But maybe that's just a biased human perspective. Because according to a paper published this week in current biology, one species, pocket gophers, may actually be farmers themselves. 

Pocket gophers excavate tunnels that can be up to 160 meters long in order to find roots to munch on. But doing all that digging requires a ton of energy and there's not actually a ton of food growing under the surface. 

In fact, just taking into account the number of roots in the soil and how much energy each of those roots can provide, it seems like gophers should actually lose energy for each meter of tunnel they dig. Pretty counterproductive. 

But in this study, researchers from the University of Flordia found that the roots in a southeastern pocket gopher tunnel were actually way bigger and healthier than would be expected based on the surrounding soil. The researchers shut gophers out of a segment of their tunnel for anywhere from 17 to 44 days.

They found that if a gopher ate all of the roots that grew in, it was enough food to provide an average of 21 percent of their daily energy needs. That's more than enough to make up the energy deficit in that digging-eating tradeoff. 

And the researchers think that that extra root growth is actually due to things the gophers are doing. By digging tunnels, the soil gets aerated in the same way tilling a garden would. That helps turn nutrients into forms that are usable to plants. Carbon, nitrogen, phosphorous, and sulfur all become more available.

And more nutrients means more plant growth. Plus by eating the roots, the gophers may actually be speeding up growth, essentially pruning them. The researchers found that the longer they kept a section of tunnel blocked off from the gophers, the slower the roots grew. They needed the gophers to keep up their growth rate.

And these specific pocket gophers don't keep their food and waste in separate parts of the tunnel like others do. They actually scatter their waste throughout the tunnel, which fertilizes the soil. This could explain why gophers spend so much energy building, maintaining, and protecting their tunnels.

They're protecting their crops. Now we don't have a fully agreed upon definition of farming, and the gophers don't plant seeds or weed their crops the way that some other farming animals do. Like leaf cutter ants fertilize their fungus farms, but they also clear away dead leaves and other encroaching fungi. 

And the marsh periwinkle snail chews on grass to encourage its favorite fungal snack to grow in the ruts left behind. But when you think about the wide range of human farming behaviors, some of them include tending to naturally growing plants like fruit trees.

So by creating favorable conditions for plant growth and then harvesting the products, pocket gophers might actually be the first nonhuman mammal known to farm. 

Now moving from underground soil to rocks in space, Mars is giving up secrets that may tell us more about how the earth was formed. It's kinda difficult to learn about the early formation of the earth. Geological activity remodels the planet constantly, and a lot of the oldest rocks get melted out of existence. 

So scientists turned to the rock record from other terrestrial planets which are less geologically active, like for example, Mars. And we happen to have access to a super old martian rock. It's a meteorite that has a bunch of different  types of rock and different components in it from a bunch of different time periods, some as far back as 4.4 billion years.

It's called Northwest Africa 7034, and it was discovered in the Sahara Desert in 2011 after being ejected from the surface of Mars somewhere around 5 million years ago. An international research team has now figured out exactly where on the surface of Mars it was ejected from, and they released their findings this week in the journal Nature Communications. 

From 55 million kilometers away on earth, they were able to pinpoint the ten kilometer area on Mars the meteorite originally came from. They used an algorithm to match properties of the meteorite to different craters that it could've come from. The algorithm took into account things like magnetic field intensity, high thorium and potassium concentrations, and location on the planet determined from previous Mars surveys.

They analyzed 90 million craters and only one matched as the possible source of the meteorite. It's a 40 kilometer wide crater called Khujirt Crater that was caused by an impact about 1.5 billion years ago. This impact brought older layers of rock to the surface and sent it flying about 30 kilometers away. Once it landed, rock from the older layers eventually melted and cooled into rock combined with newer rock in the area.

Then that area got hit again just 5 million years ago, leaving behind a 10 kilometer wide crater known as Karratha Crater, and sending rock hurdling towards Earth, specifically the rock now known as Northwest Africa 7034. The double impact explains why this meteorite contains so many different kinds of rock. from so many different time periods. 

The fact that they brought old and new rock to the surface makes the area a unique record of early crust formation on Mars. The author suggests that it could be a great target for future exploratory missions, either from orbit or with a rover that can collect rock samples. In fact future exploration may tell us a lot about not just how Mars formed, but how Earth formed too, all from one single rock.

Now we can rely on algorithms to help us determine where bits of Mars were ejected from, but we don't necessarily enjoy when algorithms are customer service representatives, which is why linode doesn't leave customer support up to the robots. This scishow news video is supported by linode cloud computing.

Linode is here to make cloud computing understandable and accessible for everyone, and often that means walking you through setup and operation, so you feel like you've bought into something that you really understand. And in today's world, it can feel like we talk to robots more than people. 

When you call a business that you've worked with for years like your local electrician, you still get the robotic runaround every time. But linode won't let you scream "Representative!" into the phone for hours. Instead, they have award-winning customer service professionals standing by 24/7 365 to help with any of your cloud computing needs.

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