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To figure out an organism's genome and DNA sequence, field biologists need big, expensive equipment in the labs. But, new high-tech devices help scientists to examine samples on the sites!

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The ability to sequence an organism's whole genome and figure out its entire DNA sequence was a pretty huge thing for biology. But you know what else was huge?

The equipment. Once they made it into the lab, those big, bulky sequencing machines were never leaving the work bench again. And they were expensive.

Only some labs could afford them. Which left some biologists out in the cold. Those who rely on field work for their science had to think carefully about what they could send back to the lab.

But technology has come a long way. And some of those hulking bench-top machines are now pocket-sized and affordable. Which means, for the first time, researchers can bring the genetics lab to the field.

They can sample to their heart's content, even in remote, under-explored locations. Places where there is a lot of life waiting to be discovered. First, let's look at a tool that isn't used in the field yet, but can make fieldwork much easier.

A microarray is a tool used to detect the expression of thousands of genes at the same time, so researchers can learn a lot about one organism or an entire population from a single sample. Microarrays are slides that are printed with tens of thousands of tiny spots of DNA in specific positions. Those bits of DNA can match up with messenger RNA in a sample.

Since mRNA is made when genes are expressed, microarrays tell us which genes in a sample are active and which aren't. These tools are relatively accessible and rely on open-source software, so you don't have to blow all your funding to use them. While these aren't used directly in the field -- at least not yet -- microarrays make field research better and faster.

Knowing what genes are being expressed by what organisms can tell us what's out there. But it also gives us information about the genetic variety of an ecosystem, and even how creatures are responding to environmental changes. This is particularly important in the face of climate change.

And there's more than one tool for that. Say you need to keep an eye on what's in the water -- for example, to predict harmful algal blooms, which are becoming more common as our climate warms. If you could detect the algae's genetic material ahead of time, you might be able to see the bloom coming before you're up to your waist in it.

Environmental Sample Processors, or ESP's, are genetic sensors that can be placed in a body of water, like a lake, river or ocean. They can stay submerged for months, letting researchers collect and analyze multiple water samples. The ESP samples the water, and then uses a bunch of molecular probes to identify the genetic material that's there.

These probes are simply tiny bits of DNA or RNA that can pair with the genetic material researchers are looking for. The instrument can be accessed remotely, which allows researchers to download and analyze data in almost real-time without removing the instrument. The researchers can tell the ESP to take more samples when it detects water conditions would trigger a bloom.

For example, a sudden drop in water temperature that means nutrient-rich bottom water is moving up to the surface. This helps researchers pinpoint when just a few harmful algal cells will turn into a bloom, making ESP's useful as early warning monitoring systems for coastal waters. Currently, ESP's only function in shallow water and at mild temperatures.

But researchers are working on modifying them to be able to stand up to the intense pressures, and sometimes extreme temperatures, of the deep sea. They hope to deploy them near deep-sea hydrothermal vents to find out who's living around there, possibly capturing genetic material from new, never-before seen creatures. But while molecular probes require you to design them based on what you're looking for, the real dream is to be able to scan your surroundings and sequence the DNA of whatever you find on the spot, which is no longer limited to the likes of Star Trek.

A device called the minION. It allows researchers to sequence the long DNA or RNA fragments in real-time, using technology that can fit in your pocket. This type of sequencing works by passing nucleic acids through a tiny hole called a nanopore.

As each base passes through, there's a slight change in electrical current. The electrical signal produced gets decoded by the device in real-time, providing the specific DNA or RNA sequence. It sounds like the future!

This technique makes DNA sequencing very easy to do in the field, where before, samples would need to be preserved and processed later in the lab. It's especially useful when looking at environmental DNA in the water to see what creatures are out there. This new technology is also much more affordable than older sequencing technologies, priced about the same as an iPhone.

In fact, there's even a companion app that makes analyzing the sequenced DNA easy to do right in the field. Among other things, it makes it possible to transfer data from the sequencer without an internet connection, meaning nowhere is too remote for genetic sequencing. High-tech genetic advancements have dramatically improved field biology.

They require less time, space and money, all while bringing the genetics lab to the field. They've helped researchers take more samples and look at their data almost immediately to give them a more in-depth look at the ecosystem they're studying. These technologies can be used in under-explored locations, giving scientists a better understanding of who is living there.

Meaning they can help us discover new species, or answer questions we haven't even thought of yet. Thanks for watching this episode of SciShow, which was supported by our community of amazing Patrons. Patrons get access to neat perks, everything from behind-the-scenes photos to monthly live-streams.

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