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  • We've explored the origins of modern biology, the earth sciences, and even the sciences

  • of outer space.

  • Now it's time to put these disciplines together.

  • Starting around 1900—but picking up during the Cold Warscientists looked beyond individual

  • species and ask questions about how whole systems of living and nonliving things change

  • together over time.

  • Where geneticists looked to model evolution in the laboratory, these nature-focused, systems-thinking

  • scientists looked to bring laboratory-style researchmeaning reproducible and empiricalinto

  • the literal field.

  • It's the birth of ecology and earth systems science!

  • [Intro Music Plays]

  • As with othermoderndisciplines, ecology

  • has lots of roots in different places and times, but it became a formal science in the

  • late 1800s and early 1900s.

  • The detailed, wide-ranging, and data-driven work of Darwin, Wallace and others inspired

  • other life science researchers to travel and observe the complexities of the living world.

  • And Darwin's German hype-man, biologist Ernst Haeckel, coined the

  • word ecology, This means the study of the oikos, meaning homeor, metaphorically,

  • the environment.

  • Haeckel introduced popular readers to many environments in his masterwork of scientific

  • illustration, Art Forms in Nature.

  • But okaywhat exactly would doing a science of the environment look like?

  • It would involve studying life and the nonliving things that affect life like water and soil.

  • Mediating between living and nonliving things are nutrients like carbon, nitrogen, and oxygen,

  • which cycle in and out of organisms in different ways.

  • So early ecologists tended to include both life scientists like Haeckel and earth scientists;

  • as well as those studying evolution, like geneticists working on flies, and those studying

  • landscapes, like botanists.

  • Botanical gardens remained key places to conduct research, as did natural history museums that

  • collected bones, fossils, and preserved specimens in jars.

  • Bones could be compared to bones, leaves to leaves, and so on.

  • Mexican-American Ynes Mexia started fieldwork at the age of fifty oneand went on to

  • collect more than 150,000 wild botanical specimens, at least five hundred of which were new species.

  • And her work is still being processed!

  • Meanwhile, Russian-Ukrainian polymath Vladimir Vernadsky pioneered ways

  • to analyze nature holistically.

  • One was geochemistry, or using the methods of chemistry to understand minerals.

  • Another was biogeochemistry, which analyzes living and nonliving processes.

  • Vernadsky promoted a new mode of ecological thought: what is life?

  • At the highest level of analysis, it's the whole observable-by-humans planet!

  • The nonliving, or abiotic, dimension of the earth is the geosphere, which cradles and

  • interacts with the biosphere.

  • Vernadsky even proposed another level: the noösphere, or totality

  • of human thought, which he imagined cradled by and interacting with the lower levels.

  • Vernadsky also pioneered radiogeology, the study of radioactive elements in the crust.

  • Aaand he worked on the Soviets' atomic bomb.

  • Because sooooo many scientists worked on weapons.

  • Around the time that Vernadsky worked, ecology

  • became a discipline.

  • English botanist Arthur Tansley first obsessed over ferns, and later all plants.

  • He wanted to map all of the different types of vegetation across England, and he thought

  • other botanists should want the same.

  • So he founded clubs to map plant types.

  • And in 1913, Tansley organized the first professional society of ecologists, and he became the first

  • editor of the Journal of Ecology.

  • In terms of epistemic work, Tansley is remembered for one word: ecosystem.

  • See, scientists are pretty into units.

  • Tansley reframed the study of nature: instead of groups of individual living thingssay,

  • some birds in some treesit's the study of dynamic interactions between living and

  • nonliving things in one area.

  • Tansley's rival was American botanist Frederic Clements.

  • His epistemic contributions similarly involved what ecologists should study.

  • Clements argued that plant formations are best studied as units called communities.

  • A plant community is not just like a living organism: it is an organism!

  • It's born, grows, eats, and dies.

  • And Clements focused on how an area's climate determined which plants will grow there.

  • For example, a pond dries up over and becomes first a meadow, then a forest.

  • This was a version of an older concept, ecological succession, how the makeup of groups of organisms

  • in areas change over time.

  • But Clements championed his own, highly deterministicclimax communityversion of succession.

  • Tansley haaated this, arguing that nature is messier than Clements described in his work.

  • Tansley and Clements fought about ecology from 1905 until World War Two.

  • But both agreed that ecologists should promote conservation, or working to actively maintain

  • the health of nonhuman environments.

  • Conservation has its own history.

  • But ecology as a way of making knowledge has always been tied to conservation as an ethos

  • or practice—a way of doing something in the world.

  • This isn't a “technologyin the same way the lightbulb or computer is.

  • But the practice of conserving ecosystems is as important as lighting up cities or making

  • sicc memes.

  • To name just two wins in conservation, U.S. President Teddy Roosevelt created the National

  • Park system in the first decade of the 1900s, helping preserve vast areas of forest, desert,

  • and other wilderness.

  • And in 1972, the Marine Mammal Protection Act helped radically lessen the threat humans

  • present to dolphins, seals, and whales in U.S. watersalthough the threat remains.

  • But early ecologists didn't have all the

  • tools they needed.

  • For many of those, we can thank English-American polymath George Evelyn Hutchinson, his student,

  • Howard T. Odum, and Howard's older brother, Eugene.

  • Take us there, Thoughtbubble! After World War Two, they established ecosystem

  • ecology as a richly quantitative discipline.

  • They took Tansley's essential insight and ran with it, showing how to model the processes

  • at work in a given ecosystem.

  • All three men used experiments to generate mathematical models tracing the flow of energy

  • from nonliving sources, into primary producers like plants, primary consumers like herbivores,

  • and then into meat eaters and the eaters of dead thingsfungi and bacteria.

  • And he was the first to use very small amounts of radioactive particles as tracers to map

  • how particles move in a pond, including how plants take up radiation.

  • The Odums went on to develop this radiotracer-as-tool technique further, which is used today to

  • study how water moves and how pollutants move through environments.

  • They also helped establish radiation ecology, which studies the effects of radioactive materials

  • on living systems.

  • The Odums researched ecosystems from coral reefs in the Pacific to riversheds in Georgia.

  • Eugene Odum taught at the University of Georgia, in fact, from 1940 to 2002.

  • He pushed all biology students to study ecologywhich got a big laugh in the forties, but is now

  • part of the common sense of the life sciences.

  • Of course you have to study how weather, plants, animals, and soils relate!

  • And Eugene deftly summarized, with some help from his bro, much of their work in the book

  • Fundamentals in Ecology in 1953.

  • This book unified ecology, offering a range of useful techniques to all budding plant

  • scientists, animal scientists, and rock scientists.

  • For years, it was the only textbook in ecology.

  • And, revised, it's still used as a textbook in many classes today!

  • Thanks ThoughtBubble! The Odums' work encompassed observational

  • and empirical methods, some of which were focused on specific parts of ecosystems.

  • But the Odums were also pioneers of a sub-discipline of ecosystem ecology,

  • confusingly called systems ecology.

  • This is the holistic study of complex living systems as systemsincluding the interactions

  • among their nonliving inputs, their boundaries, how they adapt to new conditions, how they

  • interact with other systems, and the unpredictable, emergent properties they exhibit.

  • Inspired by Hutchinson's work on feedback loops, Howard modeled how energy flows within

  • ecosystems.

  • He borrowed concepts from thermodynamics and computing in his work on systems ecology.

  • You could say the Odums were trying to understand ecosystems as really complex, but not random,

  • machines.

  • In fact, in the 1960s, they applied multiple times for money from NASA to engineer self-regulating,

  • closed ecosystems of algae and plankton—a whole biosphere in miniature.

  • These would serve as life-support systems for astronauts.

  • They based their proposals on their study of the energy flows of the coral atoll Enewetak

  • in the Marshall Islands.

  • Alas, NASA thought their plans were too complex, and the Odums returned to earthly matters.

  • The question of life in space intrigued scientists

  • modeling the relationships between energy, chemicals, and organisms.

  • In the 1960s, NASA hired English scientist James Lovelock to build instruments to analyze

  • the atmosphere of Marsand look for signs of life.

  • Lovelock thought about why Mars' atmosphere has certain properties, different from ours,

  • and what that means for the evolution of life.

  • He arrived at the Gaia Hypothesis, named after the Greek earth goddess.

  • This says the earth's biogeosphere is self-regulating, within broad limits: living things, air, rocks,

  • and water interact in complex ways so that living things can stick around.

  • This was a hugely controversial claim!

  • It suggested a self-awareness to the earth.

  • But Lovelock's evidence for a regulatory function between what's in the atmosphere

  • and oceans and what's alive, breathing that air or water, is pretty convincing.

  • And he picked up major support from revolutionary biologist Lynn Margulis.

  • She discovered that some of the tiny organs inside cellslike cells' power stations,

  • mitochondria and chloroplastsused to be free-floating bacteria that evolved to live

  • entirely within larger organisms.

  • This idea, endosymbiosis, was also huge controversialnot because it was too touchy-feely, but because

  • it seemed to have nothing to do with the work of Darwin!

  • But Margulis also demonstrated lots of evidence.

  • So biologists and ecologists were confronted with complex systems over here,

  • superorganisms over therecommunitiesall the way up, and all the way down in scale.

  • Today, this shift is captured in the name of the meta-discipline that applies systems

  • thinking across many sciences: earth systems science.

  • This means understanding how living and nonliving processes relate, and looking at the entire

  • earth as one very bigbut not infinitehouse.

  • This is a house we humans can wreck.

  • Andwe hoperepair.

  • So just as the life sciences had to scale up to ecosystems and then the entire earth,

  • they also had to take into account how humans affect ecosystems and earth systems.

  • A new branch, human ecology, developed.

  • If that all sounds a bit like what Vernadsky said a hundred years agoyou're right!

  • Human thought, nonhuman life, rocks, waterall connected.