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a revolution is underway a
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transformation in our understanding of
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life on Earth using new technologies
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reaching for new insights scientists are
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writing a new history of the animal
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kingdom by studying nature's unsung
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heroes creatures almost beyond our
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imagination they're uncovering the
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deepest roots of our own origins
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whole field is open again we're back to
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investigating where we came from it is
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the story of animal life and how it came
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to be an epic tale that can finally be
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told
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like all good stories it begins with a
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quest for basic answers about life
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itself where did we come from
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was there a first animal one that gave
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rise to us all I'm obsessed with
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learning where we came from where did
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the organisms come from the caber eyes
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to complex animals incredibly a first
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animal group has now been identified a
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mysterious creature whose descendants
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are still alive today they're just so
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alien so old so ancient and so different
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to anything else you find they're just
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magnificent
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join us now on the search for the first
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true animal the primal ancestor that
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pioneered the shape of life
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biologist Rudy Raph doesn't appear to be
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much of a revolutionary but he is a key
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scientist who is helping to forge a new
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understanding of how animals arose on
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earth he's helping to reconstruct a
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radically new history of animal life 50
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years ago people would have thought we
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knew all of there was about animal
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evolution about the relations of animals
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to each other Oldfield is open again
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genes and paleontology have opened these
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problems back up and we're we're back to
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investigating where we came from Raph
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and his colleagues are wrestling with
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mysteries that have perplexed scientists
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for centuries the questions are as
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daunting as they are profound
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[Music]
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how did life on earth become so diverse
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encompassing millions of species
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[Applause]
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how did animals come to be designed the
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way they are and what are their shapes
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tell us of their history
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[Music]
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how has the struggle to survive molded
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the shape of life and what can we learn
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from the survivors
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and how did we humans arise from the
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complex tapestry of life on earth this
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is really a very exciting time to be
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looking at evolutionary biology there
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are three strands to the story that are
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beginning to grow and weave into each
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other to produce a really strong story
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the first is paleontology which is
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beginning to make new discoveries and
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has filled in a lot of gaps in our
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knowledge of extinct animals scientists
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are also deciphering the genetic secrets
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of how animals living today have
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acquired their shapes
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[Music]
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and finally we can combine DNA sequences
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and Anatomy to construct the animal
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family tree in powerful new ways over
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the past roughly two decades the tools
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are there coming from genetics and
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molecular biology recombinant DNA work
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and classical embryology and
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paleontology all these different fields
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are all coming together and all of a
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sudden people are talking to each other
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who never had any opportunity or reason
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to before
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[Music]
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in their quest to peel back the past
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Eon by eon layer-by-layer researchers
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are traveling the world finding clues in
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lands strange and familiar the case that
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they're building the story they're
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writing is filled with unpredictable
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twists and turns
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it is a voyage through time
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an adventure in Natural History a story
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full of unknown characters and unsung
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heroes this is not some agents no stupid
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creature this is a survivor it's a
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survivor for good reason you don't last
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500 million years if you're poorly
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adapted to understand what is being
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discovered is to see life exposed as it
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never was before
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in all its horror and its beauty from
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the most delicate creations to the most
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complex
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we will meet fantastic animals that
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seemed at times to border on the surreal
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we will encounter the monsters
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the mysterious
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[Music]
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and the truly marvelous
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but our story begins with a simple
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question was there an animal Eve that
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gave rise to all of this diversity
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it's an ancient puzzle that scientists
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have finally begun to solve the search
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begins in Indonesia a nation of 17,000
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verdant islands strung like jewels
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between the Pacific and Indian Oceans it
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is home to more than 200 million people
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of diverse ethnic backgrounds
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it also nurtures an enormous diversity
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of other living things
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more different kinds of creatures live
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here than just about anywhere else on
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earth
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tropical forests cling to the steep
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slopes of volcanoes which rose from the
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bottom of the sea
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the result is a land that spawned new
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species with abandon from some of the
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world's smallest primates - one of the
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greatest of great apes
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[Music]
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this kaleidoscope of life is a lure for
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scientists especially those trying to
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sort out the evolution of animal life
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[Music]
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among them is Spanish born biologist
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Christina Diaz she hasn't come to the
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island of Sulawesi for its lush forests
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but for the diverse community that
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thrives in its undersea domain
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for me a biologist to be here in
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Sulawesi it's an event beyond my dreams
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as it is one of the richest places on
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earth in terms of biodiversity and this
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makes me feel like I'm one of the
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luckiest people in the world
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just below the calm and tranquil waters
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of Sulawesi lies a bustling world it is
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a place we can visit only briefly but
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it's home to a spectacular variety of
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animal life
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[Music]
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down here you are in another world I
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feel so comfortable and so part of
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something very large it's a world of
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colors and sounds that is very hard to
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describe it's almost like a silence but
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it's silent that is full of crackling
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and full of life
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in this thriving seascape live familiar
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animals as well as others both
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perplexing and alien
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[Music]
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where others might see a collage of
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colors and shapes in these waters Diaz
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sees pattern and order I am a taxonomist
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and as a taxonomist what we do is that
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we attempt to organize the incredible
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diversity of life that surrounds us Diaz
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is part of a long line of scientists and
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philosophers determined to organize life
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and so make sense of it
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this desire to categorize living things
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is almost as ancient as science itself
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Aristotle was perhaps the first to
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codify a system for classifying animals
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by their internal and external
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similarities during the mid 1700s the
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Swedish botanist carolus linnaeus
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developed a standard method for naming
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organisms he introduced the idea of
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genus and species to him animal
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organisms were perfect and unchangeable
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creations
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[Music]
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a hundred years later Charles Darwin
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shook the world
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his theory said that species could
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actually change over time what's more it
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also implied that all animals may have
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descended from a single common ancestor
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Darwyn suspected if only we could travel
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millions and millions of years back in
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time that we could witness the birth of
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the Earth's first animal in the
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beginning the earth was devoid of living
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things then about three and a half
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billion years ago something completely
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new appeared life for two and a half
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billion years single-celled organisms
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dominated the earth they were minuscule
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creatures completely enclosed in a
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fragile membrane these were living
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pulsing beings but they weren't animals
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somehow cells developed a language that
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allowed them to work together when they
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did it was a turning point for life on
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Earth
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the very first animal had begun to take
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shape but what was this first creature
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the first animal would really have been
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something very simple you would not have
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had a head a brain a mouth or any
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internal organs not even bones it would
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have been something made up of a bunch
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of cells a bunch of animal cells those
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cells would have to cooperate to work
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together for the common good of the
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animal
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[Music]
00:14:02
incredibly such an animal still exists
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and it thrives in these waters
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and that is why Diaz has come to
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Indonesia local legend hands bar tuna is
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a retired medical doctor affectionately
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known as the grandfather of diving in
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northern Sulawesi but tuna knows exactly
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where Diaz confined what she's come to
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study and points the area out of her on
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there and there's a fairly deep trough
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here and here the marioneta he tells her
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that she must go to the foot of a
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volcano called Manado tua she must look
00:14:54
for a reef that ends in an underwater
00:14:56
wall plunging hundreds of feet into the
00:14:59
depths there she will find what she
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seeks
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[Music]
00:15:13
ever since Darwin put forth his theory
00:15:17
of evolution scientists like Diaz have
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puzzled over animal origins at long last
00:15:23
she and others think they have found a
00:15:26
creature that links us to a moment in
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deep time - the first animals of Earth
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[Music]
00:15:36
it is a creature that is somewhat alien
00:15:38
in its appearance a being without a
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nervous system muscles limbs or a brain
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its body is defined by a loose
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assemblage of cells it is the ancient
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sponge
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when I encounter a sponge it just takes
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my breath away I just want to stop and
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look you know they're just so alien so
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old I mean so ancient and so different
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to anything else you find in the bottom
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of the sea just they're so alien forms
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of life you know and at the same time
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they're so present that is just it just
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leaves me in awe
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I think they're beautiful that original
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they are mysterious they have lots of
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secrets that we have to unveil you see
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and that for me it's an attractive
00:16:44
things they keep a lot of Secrets that I
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think are very important
00:16:50
[Music]
00:17:00
sponges don't give up their secrets
00:17:02
easily their apparent simplicity is both
00:17:06
provocative and perplexing at a distance
00:17:11
they seem solid but a closer look
00:17:17
reveals a labyrinth of tiny holes
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tunnels and chambers unlike our bodies
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sponges have no definitive shape they
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are as varied as their many habitats
00:17:46
scientists have described more than nine
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thousand different species of sponge
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they thrive in salt and freshwater
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environments around the world
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turning up in the most bizarre and
00:18:01
unexpected places from the frigid waters
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of the poles to the warm seas of the
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tropics Christina Diaz recognizes the
00:18:19
sponge as a vibrant animal but for
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centuries scientists have debated
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whether in fact this was true
00:18:27
[Music]
00:18:32
even today it stretches the imagination
00:18:35
to think of this odd organism as an
00:18:38
animal to the untrained eye it barely
00:18:41
seems alive at all when we think of
00:18:47
animals we come to up something entirely
00:18:49
different animals move
00:18:55
they feed themselves
00:19:04
they reproduce uncaf they're young
00:19:10
they engage in fierce territorial
00:19:12
battles
00:19:15
in comparison a sponge seems lifeless if
00:19:19
it is an animal
00:19:20
it certainly conceals its true nature
00:19:34
[Music]
00:19:35
to help her unravel the mysteries of the
00:19:38
sponge Diaz has teamed up with biologist
00:19:41
and conservationist Marc Wortman
00:19:45
hi
00:19:52
[Music]
00:20:00
hi Christina welcome to Wanaka
00:20:11
Herman has spent years as a marine
00:20:14
researcher in Indonesia he knows these
00:20:16
waters and the reefs they Harbor today
00:20:21
Diaz has her sights on a reef wall that
00:20:24
drops hundreds of feet into the deep
00:20:26
together she and Edmund will descend the
00:20:28
cliffs searching for sponges that live
00:20:39
the samples they collect will provide a
00:20:42
window into a fascinating world the
00:20:45
microscopic realm where sponges are most
00:20:48
active and dynamic
00:20:58
sponge cells are unique in the animal
00:21:01
kingdom but in order to study their
00:21:04
miraculous abilities Diaz and Edmund
00:21:06
will have to gather living samples and
00:21:09
transport them to the lab William
00:21:15
sponges to study in the lab and so we
00:21:17
have to collect specimens but we need to
00:21:21
just cut a small section to be examined
00:21:23
and because it doesn't have a nervous
00:21:25
system we are not really hurting it in
00:21:28
time the cut area will grow again as if
00:21:31
nothing had happened to it all animals
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rely on cell to cell communication but
00:21:41
Diaz and others have been able to show
00:21:42
that sponge cells have a unique way of
00:21:45
working together to witness their
00:21:48
abilities is to be amazed
00:21:58
unlike most of our cells those of
00:22:02
sponges retain a special freedom over
00:22:07
several hours they begin to come
00:22:10
together building many new sponges
00:22:16
[Music]
00:22:48
while the sponge appears strikingly
00:22:51
different from other animals it does
00:22:53
share some basic hallmarks its cells are
00:22:57
held together in part by a protein
00:22:59
called collagen which is possessed by
00:23:01
all animals on earth collagen which is
00:23:05
the most abundant protein in the animal
00:23:08
world forms the supportive system for
00:23:12
the sponge body so even in the form of
00:23:15
small fibers that all sponges have that
00:23:18
give support to the cells or in the form
00:23:22
of strong and stout fibers that give
00:23:26
rigidity and support that the sponge is
00:23:31
to achieve larger sizes most people when
00:23:38
they think of a sponge they think on
00:23:41
their bath sponge and when you have a
00:23:43
bath bone in your hand you're holding is
00:23:46
a soft skeleton that is made of collagen
00:23:51
but unlike the bath variety many sponges
00:23:55
aren't soft at all in addition to the
00:23:59
soft collagen of the bath sponge many
00:24:01
have millions of brittle crystalline
00:24:03
spicules embedded in their bodies
00:24:08
spicules are microscopic structures that
00:24:11
help give a sponge its rigidity and for
00:24:15
[Music]
00:24:19
speakers are an incredible tool for us
00:24:22
today to identify most of the sponges
00:24:26
that are living in the oceans you can
00:24:29
identify a species or a group of sponges
00:24:32
not only by the type and the size of the
00:24:35
speaker's they have but the way that
00:24:37
they are arranged in this sponge body
00:24:45
for most sponges the glassy spicules act
00:24:48
as a kind of fingerprint magnified their
00:24:52
dazzling array of shapes and sizes are
00:24:54
as beautiful as they are unearthly
00:24:59
[Music]
00:25:06
[Music]
00:25:27
if the sponge is indeed an animal it
00:25:31
must eat to survive how does it feed
00:25:34
itself when it has no obvious mouth a
00:25:39
sponge is actually a fantastic pump
00:25:43
which requires an incredible
00:25:45
coordination of cells to function it's a
00:25:48
living filtering machine it lives by
00:25:53
sucking in water and filtering out food
00:25:56
particles these seemingly motionless
00:26:00
creatures are actually working extremely
00:26:02
hard in order to feed imagine that to
00:26:07
get an ounce of food a sponge have to
00:26:10
pump over that ton of water through
00:26:12
itself now can you imagine doing that
00:26:15
yourself drinking a ton of water to get
00:26:17
an ounce of food to your body Diaz has
00:26:22
studied sponges for decades yet she's
00:26:25
never seen them feed in the wild until
00:26:28
now few people have
00:26:30
[Music]
00:26:34
to make the invisible visible Diaz
00:26:38
injects a harmless colored dye into the
00:26:40
water near the body of a sponge one of
00:26:46
the ways we can test for the rate of
00:26:48
water flow that move through the sponge
00:26:50
body is to inject a colored dye and
00:26:54
measure the speed at which it is pumped
00:26:58
through the sponge actually for me this
00:27:02
is the first time I've done this
00:27:04
and I've been really looking forward to
00:27:06
the opportunity for years I'm so excited
00:27:10
to try this experiment
00:27:14
[Music]
00:27:15
when I start seeing the color dye coming
00:27:19
out for the sponge in less than two
00:27:22
seconds from when it was applied I could
00:27:25
not believe my eyes
00:27:27
this
00:27:29
steady and strong continuous flow of
00:27:32
water continuously coming out of the
00:27:35
sponge was an incredible realization of
00:27:38
the dynamic existence of this organism
00:27:56
it's an incredible sight to witness
00:28:02
[Music]
00:28:14
these ghostly exhalations are proof that
00:28:18
the sponge is actively pumping with no
00:28:22
mouth
00:28:23
it sucks water directly through its
00:28:25
sponge like body walls which are shot
00:28:27
through with millions of narrow canals
00:28:29
and tiny chambers
00:28:34
how does it do it what secrets hide
00:28:36
within the belly of this beast the best
00:28:41
way to find out is to enter one of the
00:28:43
many portals into the sponges secret in
00:28:46
a world drifting along with countless
00:28:54
single-celled organisms we feel the tug
00:28:57
of a current
00:29:02
in the wonderland within this spongy
00:29:05
cells all work for the common good for
00:29:08
they do it in wildly different way
00:29:13
as the current drawers as on we pass
00:29:16
sponge cells that are making new
00:29:18
spicules
00:29:29
the walls themselves are treacherous
00:29:31
they can simply engulf their unfortunate
00:29:34
prey
00:29:53
[Music]
00:29:55
as we are drawn through ever narrower
00:29:58
passages the current slows
00:30:01
until we burst into one of the sponges
00:30:04
millions of tiny beating hearts these
00:30:09
are Kohima sites cells whose whip-like
00:30:12
flagyl i
00:30:16
the flow quickens again as it wisps it
00:30:18
away
00:30:21
through the labyrinth of canals that
00:30:23
lead out
00:30:25
into the sponges central cavity
00:30:37
what once seemed barely alive is
00:30:41
actually a living animal more complex
00:30:43
than we could ever have imagined the
00:30:51
sponges pumping does more than satisfy
00:30:53
its hunger for food
00:30:55
in fact it's sex life depends on pumping
00:30:59
as well
00:31:01
half a billion years ago these were the
00:31:04
very first animals to reproduce sexually
00:31:06
the first to combine sperm and egg to
00:31:10
create offspring set adrift some sperm
00:31:18
will be lucky enough to enter another
00:31:20
sponge of the same species if the sperm
00:31:24
are truly fortunate they will fertilize
00:31:26
the eggs within
00:31:32
[Music]
00:31:39
our intimate tour of the sponge reveals
00:31:43
a creature full of surprises from
00:31:45
feeding to reproduction it engages in
00:31:48
elaborate behavior more than a mere
00:31:52
aggregation of cells the sponge is in
00:31:54
fact a living thriving animal
00:32:04
though of ancient design sponges
00:32:07
continue to thrive in today's diverse
00:32:09
and crowded world in fact they play a
00:32:12
vital role in the lives of many other
00:32:15
animals since they first appeared
00:32:24
sponges have formed a multitude of
00:32:26
strange symbiotic relationships these
00:32:30
sea cucumbers just a few inches long
00:32:33
take advantage of the sponges pumping
00:32:36
action as food particles that are too
00:32:41
large for the sponge to absorb flow by
00:32:43
the sea cucumbers use their tentacles to
00:32:46
snag them it's a free lunch
00:32:50
all thanks to a sponge
00:32:56
on Indonesia's crowded reefs sponges
00:32:59
provide sanctuary to a whole host of
00:33:01
different creatures small species of
00:33:05
fish hide within their walls or perch
00:33:08
cryptically upon their turrets
00:33:11
[Music]
00:33:23
in return for a safe haven some animals
00:33:27
are willing to give up their freedom
00:33:28
permanently
00:33:33
this little sponge is called Venus's
00:33:36
flower basket as it grows it weaves its
00:33:43
glassy spicules together sometimes
00:33:45
forming a living refuge for a pair of
00:33:48
shrimp here they mate and grow
00:33:56
and if they become too large to escape
00:33:58
they are confined forever within this
00:34:01
prism of spun glass
00:34:07
sponges unwittingly protect their animal
00:34:09
partners in other unusual ways the
00:34:18
sponge crab Clips off a piece of sponge
00:34:21
and then proceeds to wear it like a hat
00:34:29
since most sponges are inedible the crab
00:34:33
benefits from the camouflage but not all
00:34:36
sponges are so easygoing as bestop lumen
00:34:43
is a sponge that appeals its hair-thin
00:34:48
spicules are covered with tiny hooks
00:34:50
perfect for snagging a helpless crab
00:34:52
larvae specialized cells use out of the
00:34:57
sponges body migrate around its prey and
00:35:00
digest it alive
00:35:04
[Music]
00:35:06
with cells wandering in and out of its
00:35:08
body this sponge seems like a character
00:35:11
from science fiction not a likely
00:35:16
candidate for the title of the first
00:35:18
animal on earth
00:35:25
yet sponges are ancient so remarkably
00:35:29
old that scientists have often wondered
00:35:31
if they were our forebears could it be
00:35:34
that these primitive creatures so
00:35:36
different from other life-forms gave
00:35:38
rise to all the other animals including
00:35:40
us
00:35:42
[Music]
00:35:44
questions about the origin of animal
00:35:46
life have long plagued thoughtful minds
00:35:53
[Music]
00:35:57
one man who's devoted himself to
00:35:59
unraveling the mystery his Michels
00:36:02
Soviet
00:36:07
I'm obsessed with learning where we came
00:36:09
from and what I mean by that not who
00:36:12
your mother and father is or your
00:36:15
grandparents but rather where did the
00:36:17
organisms come from that gave rise to
00:36:19
complex animals like man other species
00:36:32
[Music]
00:36:35
as an evolutionary biologist so again
00:36:38
pursues these questions at America's
00:36:41
oldest Marine station the Marine
00:36:43
Biological Laboratory at Woods Hole on
00:36:45
Cape Cod in the northeastern United
00:36:48
States
00:36:50
[Music]
00:37:02
working here so Guillen was quick to
00:37:05
take advantage of promising advances in
00:37:07
genetics and computer science diatoms
00:37:12
from Nebraska their Alcala flask of it
00:37:14
do you have a look so these were
00:37:17
isolated from lakes we can get some DNA
00:37:19
from these guys by this week who could
00:37:22
probably set up some pcr experiments
00:37:23
around Thursday or Friday we should be
00:37:26
able to get a sequence from these things
00:37:27
as new technology became available so
00:37:30
Guillen decided to search the genes of
00:37:33
different animals to see if he could
00:37:35
demonstrate which one gave rise to all
00:37:37
the others
00:37:43
in looking for origins of animals
00:37:47
particularly from the perspective of a
00:37:49
molecular evolutionist you could take a
00:37:52
top-down approach in which you say I
00:37:55
recognize that the first animals
00:37:57
certainly were not cows or pigs or or
00:38:00
humans it must have been something much
00:38:02
more simple in the 1980s so again set
00:38:05
himself a challenging task to discover
00:38:07
what creature may at the base of the
00:38:10
animal kingdom
00:38:19
both of these sponges look pretty good
00:38:21
for this time of year
00:38:23
at the time some scientists suspected
00:38:26
the sponge to solve the mystery Segen
00:38:29
decided to look where few had looked
00:38:31
before
00:38:32
inside the sponges genetic code first he
00:38:36
would have to get a clear view of the
00:38:38
DNA inside their cells
00:38:40
it was laborious work a painstaking
00:38:43
process known as gene sequencing so what
00:38:47
we want to do is get
00:38:50
because the tips genetic sequences are
00:38:55
very much like blueprints for
00:38:57
constructing an organism it defines
00:38:59
everything that there is to know in
00:39:01
order to generate a body plan or to
00:39:03
carry out metabolisms or physiology you
00:39:08
have a set of genetic blueprints that
00:39:10
defines who you are I have a slightly
00:39:12
different set of genetic blueprints that
00:39:14
defines me it's very much like the
00:39:17
blueprints for building buildings or
00:39:18
cars or whatever it is you have to have
00:39:21
a plan for making we can compare the
00:39:24
genetic blueprints of different things
00:39:26
so for example I can compare the genetic
00:39:28
blueprint of of an automobile I can
00:39:32
compare that to a covered wagon and
00:39:34
there are minimal number of elements in
00:39:36
that blueprint that are common between
00:39:40
those very disparate kinds of vehicles I
00:39:44
can do the same thing in terms of
00:39:46
organisms
00:39:49
so again compared the genetic blueprints
00:39:52
of sponges to those of other organisms
00:39:58
just this physical education would be
00:40:01
enough to disrupt to disintegrate the
00:40:03
cells we won't be able to get the DNA
00:40:05
out of there pretty easily murdered he
00:40:07
focused on a gene they had in common but
00:40:10
genes are not identical and they're
00:40:12
subtle differences would be telling if
00:40:15
the genes of two animals revealed little
00:40:18
variation the animals were closely
00:40:20
related by grouping animals in this way
00:40:23
so Guillen could trace a family tree the
00:40:27
animal at the base of the tree would be
00:40:29
ancestral or basal for a long time
00:40:34
biologists argued that sponges were
00:40:37
basal to all their animals in an
00:40:39
evolutionary tree but there really
00:40:42
wasn't that any objective certain way to
00:40:46
make that claim until the advent of
00:40:49
molecular sequencing capabilities
00:40:55
in order to compare gene sequences
00:40:57
scientists must first extract the DNA
00:41:00
from the nucleus of cells the living
00:41:03
code can then be reduced to data that
00:41:05
the scientists can analyze
00:41:08
[Music]
00:41:20
there is one magical moment when DNA can
00:41:23
actually be seen with the naked eye
00:41:27
these delicate threads carry the
00:41:30
instructions for making an animal and a
00:41:33
fascinating record of the way that
00:41:35
animal evolved
00:41:39
all animals depend on these same
00:41:42
molecules to give their bodies shape and
00:41:45
form this is the very stuff of life
00:41:57
today powerful machines have taken over
00:42:00
the arduous task of analyzing genetic
00:42:03
sequences dozens of different organisms
00:42:06
can be compared at once
00:42:09
what used to take months of exacting lab
00:42:12
work can now be done in a single day
00:42:22
Michell surgeon could quickly sort
00:42:24
through reams of genetic information
00:42:28
[Music]
00:42:36
[Music]
00:42:39
we pick up jeans that we think are
00:42:41
appropriate candidates to study and we
00:42:43
precisely determine the sequence of that
00:42:46
king from a sponge and compare it to the
00:42:49
same gene that you find in a jellyfish
00:42:51
compare that to the same chain that you
00:42:53
find in a fly fish for all the human etc
00:42:58
the genes code is written in a series of
00:43:01
four letters thousands of characters
00:43:03
long
00:43:04
so again focused on one particular gene
00:43:07
to see how it chain which done varied in
00:43:10
the DNA of different animals
00:43:16
honing in on a specific region of the
00:43:19
gene he began a search that could lead
00:43:22
to insights about the evolution of
00:43:24
animal life as he churned through
00:43:28
sequence after sequence animal after
00:43:30
animal the family tree was slowly
00:43:33
revealed
00:43:40
at the end of the long and arduous
00:43:43
process so Guillen looked at the bottom
00:43:45
of the tree and found his master at the
00:43:49
base of the entire Animal Kingdom lay
00:43:52
the sponge
00:43:59
sponges lie at a critical juncture in
00:44:02
the evolution of more complex life-forms
00:44:04
on this planet they're clearly basically
00:44:09
the other animals they come from a
00:44:12
unicellular world and that's a major
00:44:14
achievement because now you can imagine
00:44:17
development of greater organismal
00:44:19
complexity in this particular state now
00:44:21
sponges had already laid the seeds for
00:44:24
the evolution of animals that you find
00:44:26
distributed throughout the animal world
00:44:28
and the very fact that sponges of why at
00:44:31
the base of the animals means that all
00:44:33
other animals in some way shape or form
00:44:35
would have come out of this simple
00:44:38
architecture of an organism so ghen
00:44:43
discovered that sponges had transformed
00:44:46
the nature of life
00:44:47
we're mainly single-celled creatures had
00:44:50
thrived before the sponge was the first
00:44:53
multicellular animal humans rabbits is
00:44:58
really a very recent event and
00:45:01
[Music]
00:45:05
if we were to run the clock of life and
00:45:08
backwards condensing hundreds of
00:45:10
millions of evolutionary steps into a
00:45:12
minute or so we would come face to face
00:45:14
with a simple organism that started
00:45:21
[Music]
00:45:26
[Applause]
00:45:29
[Music]
00:45:34
[Applause]
00:45:35
[Music]
00:45:48
[Applause]
00:45:49
[Music]
00:45:51
[Applause]
00:45:54
[Music]
00:46:13
it has been a long journey from the
00:46:18
simple body plan of the sponge
00:46:20
[Music]
00:46:22
- one as complex and sophisticated as
00:46:25
powers
00:46:26
[Music]
00:46:33
scientists are now beginning to unfurl
00:46:36
the map of life's long journey to
00:46:38
understand how creatures evolved to move
00:46:41
swim run hunt kill soar through the sky
00:46:47
and even develop the intelligence to try
00:46:49
to make sense of the world around them
00:46:54
it has been an unimaginably complex
00:46:56
Odyssey starting with a simple creature
00:46:59
routed to the ocean floor
00:47:04
it is a saga that continues even now as
00:47:11
we explore and unfold the extraordinary
00:47:15
events that gave rise to the shape of
00:47:18
life
00:47:25
[Music]
