NARRATOR: Flowering plants delight our senses; we love them in our gardens. Yet it is little appreciated that they are the basis of our food. In fact, humans would not have evolved without them.
But, for the plant, flowers are an enormous drain on limited resources, so why even have flowers?
DAVID DILCHER (Paleobotanist, University of Florida): Flowers are all about sex, that's for sure.
NARRATOR: The origin of flowers is one of botany's most enduring mysteries. Darwin called the mystery "abominable." Now two teams of scientists have set out across China to solve that mystery.
YIN KAIPU (Botanist, Chengdu Institute of Biology): Lily sargentiae.
NARRATOR: One team is searching for the clues that are held by living plants.
DANIEL J. HINKLEY (Horticulturist and Plant Explorer): Oh, my gosh! There's a lot of people that would love to be here right this moment.
NARRATOR: The other believes it has found an extraordinary fossil that could be the world's first flower.
DAVID DILCHER: That's history right there.
NARRATOR: Together, can they solve this evolutionary mystery? Tonight on NOVA, The First Flower.
Major funding for NOVA is provided by the Howard Hughes Medical Institute, serving society through biomedical research and science education: HHMI.
And by the Corporation for Public Broadcasting, and by contributions to your PBS station by viewers like you. Thank you.
NARRATOR: Flowers hold a special place in the natural world and in the human heart. But flowering plants are not just fragrant, decorative objects, they are essential to human life. Almost all our food, including wheat, corn and rice, is derived from them, as are many medicines, old and new.
But where did flowers themselves come from?
Professor Sun Ge, from China's Jilin University, is certain that early flowers evolved here, in northern China, and he is determined to find the world's first.
Not far from the border of Inner Mongolia, there is a remarkable fossil site that is revealing what the Earth looked like more than 100,000,000 years ago.
SUN GE (Paleobotanist, Jilin University): Fossils form in between the layers of sediment. Searching for fossils is like opening the pages of a book. We look page by page by page.
NARRATOR: Sun Ge searched for more than a decade, through these layers of rock, without success. One day a student dropped off three new fossils at his office. The first two were plants Sun Ge had seen before.
SUN GE: Then I looked at the third one. I was surprised. It was a very strange fossil. I was very excited.
NARRATOR: The fossil was unlike anything Sun Ge had ever seen before. At the top of two simple branches were structures that appeared to enclose seeds. An enclosed seed is a defining feature of a flower, today. Could this be an early flower?
After months of analysis, Sun Ge decided to share it with a fellow botanist in the United States. This priceless fossil, that had been buried deep in the earth for more than a hundred million years, had to endure one more burial in another kind of tomb.
Sun Ge brought the fossil to his longtime friend and colleague David Dilcher, of the University of Florida, for another opinion.
DAVID DILCHER: Yeah, it could be. It really...I think maybe you're right, that it could be.
NARRATOR: Dilcher is one of the world's leading paleobotanists, which is the study of ancient plants and their fossils. His passion is trying to understand the origin of flowers.
DAVID DILCHER: I've been looking for the earliest flowering plant in the world for, probably, 35 years.
NARRATOR: Before flowers, the Earth was covered with green plants like ferns, pines, and the now-extinct seed ferns. Their reproduction was relatively slow and inefficient. Pollination was mostly carried out by the wind.
Eventually, the fossil record shows that flowering plants came to dominate the globe. They, clearly, were the winning evolutionary strategy.
DAVID DILCHER: In numbers of species, I would guess that 95 percent of the plants that we are in contact with are flowering plants.
NARRATOR: Flowers take enormous energy for a plant to produce. They may be beautiful, but that beauty is, in one sense, a burden. So why have flowers at all?
When and how flowering plants began has long been one of botany's biggest and most beautiful mysteries. Could this strange new fossil from northern China solve that enduring mystery?
One of the best places on Earth to see the results of the evolution of flowering plants is the Hengduan Mountains in southwestern China, which span the regions of Sichuan, Hunan and Tibet. This is the most biodiverse temperate forest in the world. But to a plant lover it feels strangely familiar, because this is where many of the flowers in your garden came from.
Professor Yin Kaipu, a botanist from Chengdu, has spent his life studying the diversity of plants in the Hengduan Mountains.
YIN KAIPU: Everyone who comes here falls in love with this place. The scenery is sublime, it's beautiful. The biodiversity is so rich. It's why most of the world botanists feel that this is a living museum of plant evolution.
NARRATOR: While Sun Ge and Dilcher are studying evolution from the ancient fossil record, Yin is taking a different path. He is documenting the outcome of that evolution through a catalogue of living plants.
How did such an astonishing array of colors, patterns, shapes and sizes evolve? And how are they related?
Finding and cataloguing plants is essential to answering that question. As part of that effort, Professor Yin has been joined by Dan Hinkley, an American plant explorer.
DAN HINKLEY: China's the mother of all gardens. Whether it be the ferns, whether it be the maples, the rhododendrons, camellias, the lilies, the iris, we're in their place of origin. Right here is where they came from.
NARRATOR: Their first stop is an alpine meadow at 14,000 feet. Hinkley barely gets of the car before he sees what makes the Hengduan Mountains so special.
YIN KAIPU: Look! Lilium lophophorum.
DAN HINKLEY: Ah, Lilium lophophorum. Oh, my gosh, the first time I've ever seen this in blossom. It's fantastic. And corydalis here. Curviflora. And alium, geranium. Look at that. Should we come up? Oh, my gosh, that's just extraordinary. Lilium lophophorum—it's the first time I've seen it in flower. The petals don't completely dis-attach which makes it so exquisite.
So, we have hardy geraniums, lilies, gentians, euphorbias. There is even an edelweiss here, Leontopodium—which in mostly associated with the Alps in Europe—a spruce, picea; Potentilla; primulas; anemones. It is absolutely staggering the number of genera that we are familiar with in the garden setting that is in this small little piece of land in front of me, that has been grazed by yak and cut for the roadway. Ligularia, botrychium, which is a fern, and arenaria, it's…spirea. It goes on and on. It's absolutely staggering.
This little anenome is quite exquisite, I think, particularly so for that blue staining on the undersurface of each sepal.
YIN KAIPU: A lily; there's a lily.
DAN HINKLEY: I'm not sure, but I think that, unless you are looking at something else, I think this is another lily. The same lily. Yeah, it's lily and… Oh jeez! I just saw it. Oh, god, that is unbelievable. Oh my god, this is extraordinary.
NARRATOR: Cypripedium tibeticum is a rare species of the much sought after lady slipper orchids, named after the unusual pouch created by a modified petal.
DAN HINKLEY: Professor Yin, unbelievable! There's a lot of people that would love to be here, at this moment, sitting in yak dung. It is just amazing to see this.
NARRATOR: Whether it be finding one rare flower or one unique fossil, they are both essential parts of understanding the evolution of flowering plants.
One of the things that make the Hengduan Mountains such a rich breeding ground for plant life is the variety of climates. They like to say, here, that you can experience all four seasons in one day. Within a few hours you can drive from mountains, where the air is damp and cold, to valleys, where it's summer and there are cacti at the side of the road.
DAN HINKLEY: It is incredibly hot.
NARRATOR: The unique conditions allowed many of the flowers here to survive the last Ice Age. In other countries around the globe thousands of species of plants were stripped clean by the glaciers. The Hengduan Mountains have, in effect, served as a safety deposit box of temperate diversity.
Half a world away there is another kind of safety deposit box of plant diversity, David Dilcher's fossil collection at the Florida Museum of Natural History. These drawers hold over a quarter million fossils and document the evolution of plant life on Earth.
DAVID DILCHER: This would be a little over 300,000,000 years old. It's a totally extinct group of plants today, but it's what made up the coal age forests.
NARRATOR: The fossil record shows that, while flowering plants evolved rather late, they came to dominate the Earth.
DAVID DILCHER: The origin of flowers is a very important phenomenon in the history of the Earth. Humans are a result of this evolutionary event. We would not be here if we didn't have the products of flowering plants to eat.
NARRATOR: But clarifying the steps of flowering plant evolution has been difficult, in part because most plants decompose before they ever become a fossil. Usually only fragments remain, which is one of the things that makes this strange new fossil from China so extraordinary. The details of the plant are beautifully preserved.
Sun Ge named it Archaefructus, which refers to the fossil's ancient fruits. But how ancient is Archaefructus?
SUN GE: This is typical Jurassic rocks with the red color. From this formation we have found a lot of dinosaurs.
NARRATOR: Some of the rock layers here in northwestern China date back 150 million years to the Jurassic Period, the heyday of dinosaurs. If Archaefructus could be proven to be a Jurassic flowering plant, it would surely be one of the world's very first
ผู้บรรยาย: จาวความสุขประสาท เรารักพวกเขาในสวนของเรา แต่ มันมีน้อยนิยมว่า เป็นพื้นฐานของอาหาร ในความเป็นจริง มนุษย์จะไม่มีพัฒนา โดยพวกเขาแต่ พืช ดอกไม้จะมีท่อระบายน้ำขนาดใหญ่ทรัพยากรจำกัด ดังนั้น ทำไมได้ดอกไม้ดาวิด DILCHER (Paleobotanist มหาวิทยาลัยฟลอริดา): เป็นทั้งหมดเกี่ยวกับเพศ ที่แน่นอนผู้บรรยาย: ต้นกำเนิดของดอกไม้เป็นหนึ่งของพฤกษศาสตร์ลึกลับที่ยั่งยืนที่สุด ดาร์วินเรียกว่าลึกลับ "abominable" 2 ทีมนักวิทยาศาสตร์ได้ตั้งออกข้ามจีนแก้ปริศนานั้นยิน KAIPU (Botanist เฉิงตู สถาบันชีววิทยา): ลิลลี่ sargentiaeผู้บรรยาย: คนกำลังค้นหาปมที่มีขึ้น โดยอาศัยพืชDANIEL J. HINKLEY (Horticulturist และโรงงาน Explorer): โอ้ ฉันพุทโธ่ มีหลายคนที่ชอบที่ถูกที่นี่ขณะนี้ผู้บรรยาย: อื่น ๆ เชื่อว่า จะพบซากดึกดำบรรพ์เป็นพิเศษที่สามารถทำดอกไม้แรกของโลกดาวิด DILCHER: นั่นคือประวัติศาสตร์ที่นั่นผู้บรรยาย: กัน สามารถพวกเขาแก้ปริศนานี้วิวัฒนาการอย่างไร คืนนี้ในโนวา ดอกไม้ครั้งแรกทุนหลักสำหรับโนวาได้ โดย Howard ฮิวจ์สแพทย์ สถาบัน บริการสังคมศึกษาวิทยาศาสตร์และการวิจัยทางชีวการแพทย์: HHMIและ โดยบริษัทสำหรับการเผยแพร่สาธารณะ และสรรคุณ PBS สถานี โดยผู้ชมเช่นคุณ ขอบคุณผู้บรรยาย: ดอกไม้ถือเป็นสถานที่พิเศษ ในธรรมชาติ และในมนุษย์ แต่จาวไม่เพียงหอม ตกแต่งวัตถุ จะจำเป็นสำหรับชีวิตมนุษย์ เกือบทั้งหมดของอาหาร ข้าวสาลี ข้าวโพด และ ข้าว จะได้รับมาจากพวกเขา เป็นยามาก เก่า และใหม่แต่ดอกไม้ตัวเองมาจากไหนSun Ge ศาสตราจารย์ มหาวิทยาลัยจี๋หลินของจีน ได้แน่นอนว่า ดอกไม้ต้นพัฒนาในภาคเหนือของจีน ที่นี่ และกำลังตั้งใจหาแรกของโลกไม่ไกลจากเส้นขอบของมองโกเลีย มีไซต์ฟอสโดดเด่นที่จะเผยให้เห็นโลกที่ดูเหมือนมากกว่า 100,000,000 ปีที่ผ่านมาGE SUN (Paleobotanist มหาวิทยาลัยจี๋หลิน): ซากดึกดำบรรพ์แบบฟอร์มระหว่างชั้นของตะกอน ค้นหาซากดึกดำบรรพ์เป็นเหมือนเปิดหน้าหนังสือ เราดูละหน้า โดยหน้าผู้บรรยาย: Ge ดวงอาทิตย์ค้นหามากกว่าทศวรรษ ผ่านชั้นหิน ไม่ประสบความสำเร็จเหล่านี้ วันหนึ่งนักเรียนลดลงปิดซากดึกดำบรรพ์ใหม่สามที่สำนักงานของเขา ครั้งแรกที่เห็นดวงอาทิตย์ Ge ก่อนพืชSUN GE: แล้วฉันมองที่หนึ่งสาม ผมประหลาดใจ ซากดึกดำบรรพ์รอยได้ ผมตื่นเต้นมากผู้บรรยาย: กันได้ต่างจากสิ่งที่เคยเห็น Ge ดวงอาทิตย์ก่อน สาขาอย่างที่สองที่มีโครงสร้างที่ปรากฏให้ใส่เมล็ดพืช เมล็ดล้อมรอบเป็นการกำหนดคุณลักษณะของดอกไม้ วันนี้ นี้อาจเป็นดอกไม้เป็นต้นAfter months of analysis, Sun Ge decided to share it with a fellow botanist in the United States. This priceless fossil, that had been buried deep in the earth for more than a hundred million years, had to endure one more burial in another kind of tomb.Sun Ge brought the fossil to his longtime friend and colleague David Dilcher, of the University of Florida, for another opinion.DAVID DILCHER: Yeah, it could be. It really...I think maybe you're right, that it could be.NARRATOR: Dilcher is one of the world's leading paleobotanists, which is the study of ancient plants and their fossils. His passion is trying to understand the origin of flowers.DAVID DILCHER: I've been looking for the earliest flowering plant in the world for, probably, 35 years.NARRATOR: Before flowers, the Earth was covered with green plants like ferns, pines, and the now-extinct seed ferns. Their reproduction was relatively slow and inefficient. Pollination was mostly carried out by the wind.Eventually, the fossil record shows that flowering plants came to dominate the globe. They, clearly, were the winning evolutionary strategy.DAVID DILCHER: In numbers of species, I would guess that 95 percent of the plants that we are in contact with are flowering plants.NARRATOR: Flowers take enormous energy for a plant to produce. They may be beautiful, but that beauty is, in one sense, a burden. So why have flowers at all?When and how flowering plants began has long been one of botany's biggest and most beautiful mysteries. Could this strange new fossil from northern China solve that enduring mystery?One of the best places on Earth to see the results of the evolution of flowering plants is the Hengduan Mountains in southwestern China, which span the regions of Sichuan, Hunan and Tibet. This is the most biodiverse temperate forest in the world. But to a plant lover it feels strangely familiar, because this is where many of the flowers in your garden came from.Professor Yin Kaipu, a botanist from Chengdu, has spent his life studying the diversity of plants in the Hengduan Mountains.YIN KAIPU: Everyone who comes here falls in love with this place. The scenery is sublime, it's beautiful. The biodiversity is so rich. It's why most of the world botanists feel that this is a living museum of plant evolution.NARRATOR: While Sun Ge and Dilcher are studying evolution from the ancient fossil record, Yin is taking a different path. He is documenting the outcome of that evolution through a catalogue of living plants.How did such an astonishing array of colors, patterns, shapes and sizes evolve? And how are they related?Finding and cataloguing plants is essential to answering that question. As part of that effort, Professor Yin has been joined by Dan Hinkley, an American plant explorer.DAN HINKLEY: China's the mother of all gardens. Whether it be the ferns, whether it be the maples, the rhododendrons, camellias, the lilies, the iris, we're in their place of origin. Right here is where they came from.NARRATOR: Their first stop is an alpine meadow at 14,000 feet. Hinkley barely gets of the car before he sees what makes the Hengduan Mountains so special.
YIN KAIPU: Look! Lilium lophophorum.
DAN HINKLEY: Ah, Lilium lophophorum. Oh, my gosh, the first time I've ever seen this in blossom. It's fantastic. And corydalis here. Curviflora. And alium, geranium. Look at that. Should we come up? Oh, my gosh, that's just extraordinary. Lilium lophophorum—it's the first time I've seen it in flower. The petals don't completely dis-attach which makes it so exquisite.
So, we have hardy geraniums, lilies, gentians, euphorbias. There is even an edelweiss here, Leontopodium—which in mostly associated with the Alps in Europe—a spruce, picea; Potentilla; primulas; anemones. It is absolutely staggering the number of genera that we are familiar with in the garden setting that is in this small little piece of land in front of me, that has been grazed by yak and cut for the roadway. Ligularia, botrychium, which is a fern, and arenaria, it's…spirea. It goes on and on. It's absolutely staggering.
This little anenome is quite exquisite, I think, particularly so for that blue staining on the undersurface of each sepal.
YIN KAIPU: A lily; there's a lily.
DAN HINKLEY: I'm not sure, but I think that, unless you are looking at something else, I think this is another lily. The same lily. Yeah, it's lily and… Oh jeez! I just saw it. Oh, god, that is unbelievable. Oh my god, this is extraordinary.
NARRATOR: Cypripedium tibeticum is a rare species of the much sought after lady slipper orchids, named after the unusual pouch created by a modified petal.
DAN HINKLEY: Professor Yin, unbelievable! There's a lot of people that would love to be here, at this moment, sitting in yak dung. It is just amazing to see this.
NARRATOR: Whether it be finding one rare flower or one unique fossil, they are both essential parts of understanding the evolution of flowering plants.
One of the things that make the Hengduan Mountains such a rich breeding ground for plant life is the variety of climates. They like to say, here, that you can experience all four seasons in one day. Within a few hours you can drive from mountains, where the air is damp and cold, to valleys, where it's summer and there are cacti at the side of the road.
DAN HINKLEY: It is incredibly hot.
NARRATOR: The unique conditions allowed many of the flowers here to survive the last Ice Age. In other countries around the globe thousands of species of plants were stripped clean by the glaciers. The Hengduan Mountains have, in effect, served as a safety deposit box of temperate diversity.
Half a world away there is another kind of safety deposit box of plant diversity, David Dilcher's fossil collection at the Florida Museum of Natural History. These drawers hold over a quarter million fossils and document the evolution of plant life on Earth.
DAVID DILCHER: This would be a little over 300,000,000 years old. It's a totally extinct group of plants today, but it's what made up the coal age forests.
NARRATOR: The fossil record shows that, while flowering plants evolved rather late, they came to dominate the Earth.
DAVID DILCHER: The origin of flowers is a very important phenomenon in the history of the Earth. Humans are a result of this evolutionary event. We would not be here if we didn't have the products of flowering plants to eat.
NARRATOR: But clarifying the steps of flowering plant evolution has been difficult, in part because most plants decompose before they ever become a fossil. Usually only fragments remain, which is one of the things that makes this strange new fossil from China so extraordinary. The details of the plant are beautifully preserved.
Sun Ge named it Archaefructus, which refers to the fossil's ancient fruits. But how ancient is Archaefructus?
SUN GE: This is typical Jurassic rocks with the red color. From this formation we have found a lot of dinosaurs.
NARRATOR: Some of the rock layers here in northwestern China date back 150 million years to the Jurassic Period, the heyday of dinosaurs. If Archaefructus could be proven to be a Jurassic flowering plant, it would surely be one of the world's very first
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