The most poignant piece of writing I’ve ever seen sits in a glass case in the British Library at Kings Cross, London. It’s the last page of the diary of Robert Scott, leader of the doomed British mission to be the first to reach the South Pole. Though Scott and his team did reach the heart of the Antarctic continent on Jan. 17, 1912, they’d been soundly beaten by a Norwegian team lead by Roald Amundsen and, assailed by bad weather and poor planning, ultimately perished two months into their return journey.

The yellowed page sits beside a sister volume, which is opened to an entry from happier times, with neater font and cheerier prose. The contrast is a testament to both the terrific challenges of exploration at the limits of human existence, and the character of a man who knew his time at that limit was coming to its close.

Almost a century later, in the far milder climes of New Jersey, I cut my scientific teeth on an Antarctic microbe collected just a few miles from the base camp Scott used to launch his expedition. While Scott faced – and ultimately met – death, my greatest hazard was a cracked flask or an incubator that overheated my cultures. Though Scott’s mission and mine were fundamentally different, they make for striking bookends to our chronicles of living – and understanding life – at the edge of the planet.

While our tools for exploring the polar systems have advanced dramatically over the last century, major scientific questions still remain. We know that life, which has been evolving and expanding on this planet for 3.5 billion years, is incredibly resourceful, yet its ability to persist at extremes continues to surprise us. For example, just last week American scientists reported signs of life from an Antarctic lake buried under the continental ice sheet. The bacteria they discovered make up a community that thrives in total darkness, cut off from the sunlight that powers almost all life on the planet by a half-mile thick slab of ice.

By contrast, just a half a year earlier, researchers on the other side of the globe described microbes doing equally amazing things at the opposite end of the spectrum. Arctic phytoplankton were growing in shocking abundance just beneath a layer of sea ice only a few feet thick. Taking advantage of sunlight funneled down to them by pools of meltwater on the ice surface, they were producing unexpected blooms of biomass likely to have major impacts on the polar ecosystem.

Through the lens of human curiosity – the same instinct that summoned Scott southward and me labward – both these discoveries are incredibly exciting. Each, in its own way, is a sign of changing times for our planet, as our technical advances and attendant climatic shifts bring the world’s edge closer to us.

Deep-buried bacteria remind us that for everything we learn about life on this planet, much more remains undiscovered. Plankton blooms highlight a suite of knock-on effects of melting sea ice that we might not have anticipated before. And both discoveries occurred at the poles, the parts of the planet most acutely affected by climate change.

Earlier this week, the United Nations Environment Programme released a report on the future of these high-latitude locales. The report cautions world leaders to prepare now for environmental outcomes that seem more and more inevitable as we repeatedly fail to halt our emission of greenhouse gases.

For example, a thawing Arctic Ocean will open new shipping lanes and access for fisheries (pursuing fish populations that are themselves moving northward in search of cooler waters). It may also reveal substantial supplies natural resources: The United States Geological Survey estimates that 30 percent of the world’s undiscovered natural gas and 15 percent of undiscovered oil reserves are hiding in Arctic deposits.

And all these economic temptations fall at the edge of the world as we know it, in a place where we understand little about the potential dangers to ourselves of the ecosystems involved. What we can guess as biologists, though, is that while the living things at these extremes are undoubtedly toughened by harsh conditions, they are also likely to be slow-growing, incredibly unique, and sometimes quite delicate. All these traits highlight their potential vulnerability to human activity.

A hundred years after Scott’s fate highlighted the frailties of human flesh, it’s time for us to be aware of the frailties of the places we can now so easily conquer.

Holly welcomes questions, comments, and cultures of phytoplankton via email at hollyvm “at” stanford “dot” edu.