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Are flowers / flowering plants vital to all life on Earth?

Are flowers / flowering plants vital to all life on Earth?


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Not a biology student so forgive me if this is a very basic question. Are flowering plants (angiosperms) vital to all (or most) life on Earth?

In other words, if flowering plants disappeared, would all (or most) life on this planet be gone as a result?

To give a bit more context, I'm arguing with a friend who claims (from a biblical perspective) that without flowering plants life couldn't exist.


Angiosperms -- that is, flowering plants -- only evolved relatively recently on an evolutionary timescale, about 125 millions years ago. So for most of the history of life on earth there have been no flowering plants. Thus it seems highly likely that if angiosperms were to suddenly disappear, life on earth would continue. There might be a massive disruption of current terrestrial communities, but it's hard to imagine this resulting in total global extinction. In particular it seems unlikely that ocean communities would be undermined by the loss of flowering plants.


Flowering plant

The flowering plants, also known as Angiospermae ( / ˌ æ n dʒ i oʊ ˈ s p ɜːr m iː / ), [5] [6] or Magnoliophyta ( / m æ ɡ ˌ n oʊ l i ˈ ɒ f ɪ t ə , - oʊ f aɪ t ə / ), [7] are the most diverse group of land plants, with 64 orders, 416 families, approximately 13,000 known genera and 300,000 known species. [8] Like gymnosperms, angiosperms are seed-producing plants. They are distinguished from gymnosperms by characteristics including flowers, endosperm within their seeds, and the production of fruits that contain the seeds. Etymologically, "angiosperm" literally means a plant that produces seeds within an enclosure in other words, a fruiting plant. The term comes from the Greek words angeion ('case') and sperma ('seed').

  • Clades
  • Anthophyta Cronquist[2]
  • Angiospermae Lindl.
  • Magnoliophyta Cronquist, Takht. & W.Zimm.[3]
  • Magnolicae Takht.[4]

The ancestors of flowering plants diverged from the common ancestor of all living gymnosperms during the Carboniferous, over 300 million years ago, [9] with the earliest record of angiosperm pollen appearing around 134 million years ago. The first remains of flowering plants are known from 125 million years ago. They diversified extensively during the Early Cretaceous, became widespread by 120 million years ago, and replaced conifers as the dominant trees from 60 to 100 million years ago.


The origin of flowers: DNA of storied plant provides insight into the evolution of flowering plants

The newly sequenced genome of the Amborella plant will be published in the journal Science on 20 December 2013. The genome sequence sheds new light on a major event in the history of life on Earth: the origin of flowering plants, including all major food crop species. Credit: Sangtae Kim

The newly sequenced genome of the Amborella plant addresses Darwin's "abominable mystery"—the question of why flowers suddenly proliferated on Earth millions of years ago. The genome sequence sheds new light on a major event in the history of life on Earth: the origin of flowering plants, including all major food crop species. On 20 December 2013, a paper by the Amborella Genome Sequencing Project that includes a full description of the analyses performed by the project, as well as implications for flowering plant research, will be published in the journal Science. The paper is among three on different research areas related to the Amborella genome that will be published in the same issue of the journal.

Amborella (Amborella trichopoda) is unique as the sole survivor of an ancient evolutionary lineage that traces back to the last common ancestor of all flowering plants. The plant is a small understory tree found only on the main island of New Caledonia in the South Pacific. An effort to decipher the Amborella genome—led by scientists at Penn State University, the University at Buffalo, the University of Florida, the University of Georgia, and the University of California-Riverside—is uncovering evidence for the evolutionary processes that paved the way for the amazing diversity of the more than 300,000 flowering plant species we enjoy today.

This unique heritage gives Amborella a special role in the study of flowering plants. "In the same way that the genome sequence of the platypus—a survivor of an ancient lineage—can help us study the evolution of all mammals, the genome sequence of Amborella can help us learn about the evolution of all flowers," said Victor Albert of the University at Buffalo.

Scientists who sequenced the Amborella genome say that it provides conclusive evidence that the ancestor of all flowering plants, including Amborella, evolved following a "genome doubling event" that occurred about 200 million years ago. Some duplicated genes were lost over time but others took on new functions, including contributions to the development of floral organs.

The newly sequenced genome of the Amborella plant will be published in the journal Science on 20 December 2013. The genome sequence sheds new light on a major event in the history of life on Earth: the origin of flowering plants, including all major food crop species. Credit: Sangtae Kim

"Genome doubling may, therefore, offer an explanation to Darwin's "abominable mystery"—the apparently abrupt proliferation of new species of flowering plants in fossil records dating to the Cretaceous period," said Claude dePamphilis of Penn State University. "Generations of scientists have worked to solve this puzzle," he added.

Comparative analyses of the Amborella genome are already providing scientists with a new perspective on the genetic origins of important traits in all flowering plants—including all major food crop species. "Because of Amborella's pivotal phylogenetic position, it is an evolutionary reference genome that allows us to better understand genome changes in those flowering plants that evolved later, including genome evolution of our many crop plants—hence, it will be essential for crop improvement," stressed Doug Soltis of the University of Florida.

As another example of the value of the Amborella genome, Joshua Der at Penn State noted "We estimate that at least 14,000 protein-coding genes existed in the last common ancestor of all flowering plants. Many of these genes are unique to flowering plants, and many are known to be important for producing the flower as well as other structures and other processes specific to flowering plants."

"This work provides the first global insight as to how flowering plants are genetically different from all other plants on Earth," Brad Barbazuk of the University of Florida said, "and it provides new clues as to how seed plants are genetically different from non-seed plants."

Jim Leebens-Mack from UGA noted that "The Amborella genome sequence facilitated reconstruction of the ancestral gene order in the 'core eudicots,' a huge group that comprises about 75 percent of all angiosperms. This group includes tomato, apple and legumes, as well as timber trees such as oak and poplar." As an evolutionary outsider to this diverse group, the Amborella genome allowed the researchers to estimate the linear order of genes in an ancestral eudicot genome and to infer lineage-specific changes that occurred over 120 million years of evolution in the core eudicot.

The newly sequenced genome of the Amborella plant will be published in the journal Science on 20 December 2013. The genome sequence sheds new light on a major event in the history of life on Earth: the origin of flowering plants, including all major food crop species. Credit: Sangtae Kim

At the same time, Amborella seems to have acquired some unusual genomic characteristics since it split from the rest of the flowering plant tree of life. For example, DNA sequences that can change locations or multiply within the genome (transposable elements) seem to have stabilized in the Amborella genome. Most plants show evidence of recent bursts of this mobile DNA activity, "But Amborella is unique in that it does not seem to have acquired many new mobile sequences in the past several million years," stated Sue Wessler of the University of California-Riverside. "Insertion of some transposable elements can affect the expression and function of protein-coding genes, so the cessation of mobile DNA activity may have slowed the rate of evolution of both genome structure and gene function."

In addition to its utility in retrospective studies of the evolution of flowering plants, the Amborella genome sequence offers insights into the history and conservation of Amborella populations. There are only 18 known populations of this very special angiosperm in mountainous regions New Caledonia.

"Resequencing of individual Amborella plants across the species' range reveals geographic structure with conservation implications plus evidence of a recent, major genetic bottleneck," noted Pam Soltis of the University of Florida. A similar narrowing of genetic variation occurred when humans migrated from Africa to found modern-day Eurasian populations.

"The Amborella Genome and the Evolution of Flowering Plants," Science, 2013.

In addition to the paper about the nuclear genome sequence, two other papers appear in this same issue: one that reports the complete mitochondrial genome sequence of Amborella, which contains large amounts of foreign DNA resulting from horizontal transfer (Rice et al. 2013) and another that describes the novel assembly and validation of the nuclear genome using a combination of approaches that can be applied to other complex genomes of non-model species (Chamala et al. 2013).


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But that impressive quantity and diversity have made ensuring their future a costly challenge. Of the 200-odd species of orchids native to North America, more than half are threatened or endangered in some part of their range.

Several research endeavors have cropped up in the United States to better understand North America’s orchids—the largest among them a nationwide collaboration led by Whigham. To build a unified bank of research, he launched a joint effort in 2012 between the Smithsonian Institution and the United States Botanic Garden called the North American Orchid Conservation Center. The center is working with more than 50 groups and dozens of volunteers to collect samples of every native orchid species in the U.S. and Canada. Each sample gives researchers a chance to better understand how the plants germinate and reproduce.

On this overcast spring day, the orchid hunters are moving one step closer to solving these biological mysteries. Past an exposure of bedrock, beneath a tangle of brush on the cliff side above them, they find what they’ve been looking for: the delicate blossoms of the Cypripedium candidum.

“There’s so little known about many orchids,” says Whigham. “Very few of them have been studied in detail by anybody.” The center aims to address that research gap and in the process help scientists—who are going to some extreme lengths to study this enigmatic plant family—conserve and restore orchid populations across North America.

Fairy Slipper Orchid Calypso bulbosa © Nirupa Rao

Orchids begin life as seeds so minute they can only be seen under a microscope. They do not contain any stored food to fuel their growth. Instead, when seeds land in soil or on trees, they rely on a suite of host fungi nearby to supply the nutrients and other resources they require.

“You’re never going to see this fungus unless you’re looking at the [orchid] roots or you’re looking into soil with a microscope,” says Melissa McCormick, a research scientist at the Smithsonian Environmental Research Center in Edgewater, Maryland, who collaborates with Whigham. “That has meant that these orchids and these fungi are very poorly studied and not a lot has been known about them.”

That’s changing, though, as volunteers collect seeds, segments of the plant’s roots and a single leaf from native orchids and send them to the North American Orchid Conservation Center. The leaf tissue, stored in little coin envelopes, goes into a genetic bank for DNA research into the plants. Fungi are extracted from the plant roots. The lab grows the fungus in petri dishes, sequences its DNA and stores it long-term in test tubes.

There’s so little known about orchids. Very few of them have been studied in detail.

The result is a growing body of samples from across the United States and Canada—enough to help researchers study these complex interrelationships in new ways and learn how to propagate orchids with help from their symbiotic fungi.

That research has become even more important as orchids face increasing threats. Habitat loss, poaching, and deer foraging have reduced orchid numbers. Some species, Whigham says, could become viewable only in botanic gardens, like endangered animals found mostly in zoos.

Even less studied is how a changing climate will affect these plants. Wetter or drier weather could hurt the fungus in the soil, Whigham says, which could alter an orchid’s ability to germinate. Changes in seasonality, or phenology, could hinder the plants’ ability to reproduce.

The Science of Seduction

Many orchids achieve reproduction by rewarding thirsty pollinators with nectar in return for their pollen-delivery services. But about one-third of orchids use deceptive strategies to coax insects or small birds to their flower. This trickery can take many forms.

The spider orchid (Brassia caudata), with its long, limb-like petals and sepals, masquerades as the prey of female spider-hunter wasps, inducing the insects to grasp and then sting the spider-shaped flower. Before a fruitless attempt at predation is complete, the wasp bumps into a package of pollen that clings to its head.

Many orchids achieve reproduction by rewarding thirsty pollinators with nectar in return for their pollen-delivery services. But about one-third of orchids use deceptive strategies to coax insects or small birds to their flower. This trickery can take many forms.

The spider orchid (Brassia caudata), with its long, limb-like petals and sepals, masquerades as the prey of female spider-hunter wasps, inducing the insects to grasp and then sting the spider-shaped flower. Before a fruitless attempt at predation is complete, the wasp bumps into a package of pollen that clings to its head.

Some orchids, such as the stream orchid (Epipactis gigantea), use a technique called “brood-site imitation” to trick flies into laying their eggs inside the flower. The stream orchid produces a scent that mimics the smell of honeydew, a liquid produced by aphids. Some flies lay their eggs near aphid nests to give their young a ready meal when they hatch. In this case, the back of the bamboozled fly skims off some pollen from inside the flower as the insect exits the flower.

In another strategy called “food deception,” the pink lady’s slipper (Cypripedium acaule, seen here) lures a bee to a slit in its flower pouch by excreting a sweet smell. To escape the pouch, the bee must pass under the stigma, a floral reproductive organ, and then squeeze through one of two openings—each with a cache of pollen above it that hitches onto the bee’s body as it makes its escape.

One study of the early spider orchid (Ophrys sphegodes) found that warm spring temperatures can disrupt the plant-pollinator relationship. The early spider orchid lures young male bees to its flowers by emitting a scent that mimics the sex pheromone of female bees. To avoid competing with female bees for the males’ attention, the flower needs to bloom after male bees emerge from winter hibernation but before female bees do. Through evolution, these timings have synchronized, Whigham says. “But because of climate change, they’re getting out of synchrony.”

Many orchids use pollination strategies like the early spider orchid’s to lure specific insects or birds with the false promise of food or sex (see “The Science of Seduction,” above). When the deception results in an encounter, the unrewarded pollinator is loaded up with the orchid’s genetic material, poised to deposit it on the next orchid it visits. But not all pollinator-orchid relationships are known.

In 2018, conservation scientist Peter Houlihan and photographer Mac Stone set out to get proof of how the ghost orchid (Dendrophylax lindenii), one of the most well-known but inscrutable flowers on Earth, reproduces. It was long believed that the ghost orchid was pollinated by the giant sphinx moth because the insect’s proboscis, or tongue (which can unfurl to twice the length of its body), is designed to sip nectar from long-tubed flowers like the ghost orchid, but no one had ever photographed the moth in action.

Showy Lady's Slipper Cypripedium reginae © Nirupa Rao

That October, Stone found himself strapped to a cypress tree, 50 feet in the air, checking a remote camera trained on the largest known ghost orchid, the “super ghost.” It’s located in the National Audubon Society’s Corkscrew Swamp Sanctuary in the Florida Everglades. Houlihan, strapped nearby, motioned to Stone with his hands: Thumbs up? Thumbs down? Did Stone get the shot?

Stone used his phone to snap a photo of the camera’s screen and sent it to Houlihan, who gaped at what he saw. The photo showed a moth interacting with the ghost orchid. Other images showed additional species of moths. Houlihan finally had evidence that the long-held theory that only the giant sphinx pollinated the ghost orchid was wrong. The plant was not reliant on a single species of moth. Understanding the orchid’s reproductive biology may have been a difficult, years-long effort, but preserving the ghost might be a smidge easier than anyone had thought possible.

The two celebrated while strapped to the tree. An article followed in the journal Nature. One more orchid mystery put to rest—kind of. Because even as scientists delighted in the knowledge that the ghost orchid’s future was not tied to a single insect, a host of new questions—including whether the giant sphinx actually pollinates the flower or just drinks its nectar—unfurled in its wake.

There’s so much that we don’t know. But we know that when orchids show up, we’re doing something right.

Scientists like Houlihan have only begun to unravel the natural history of this vast plant family. In some cases, they’re discovering just how resilient orchids can be.

On the Eastern Shore of Maryland, McCormick is studying an orchid so rare it was thought to have vanished until it was spotted in 2009 on TNC’s Nassawango Creek Preserve. The plant (Platanthera x canbyi) is a hybrid of two orchids that are considered rare in the state: the white fringed and the crested yellow.

Deborah Landau, the TNC ecologist who helps manage the property, considers the reappearance of the orchid a sign of the plant’s vigor. The last recorded sighting of the lemon-colored orchid had been 18 years earlier—just after a wildfire burned through the landscape. There had been no sign of the plant since. Until suddenly—after controlled burns—the plant was spotted thriving on a former loblolly pine plantation that had been clear-cut and then restored to ecological health.

“It’s just crazy to think that these plants want exact factors,” says Landau. “But we do a fire and boom! When the right conditions are there, they come back. It just gives me a lot of hope.”

Spider Orchid Brassia caudata © Nirupa Rao

McCormick, along with a postdoctoral fellow in her lab, Ida Hartvig, is studying hybrid orchids from Nassawango Creek and other landscapes, including TNC’s Green Swamp Preserve in North Carolina. They are analyzing, among other things, how orchid hybrids form and how and what hybrids suggest about the development of new species.

“If, for example, the hybrid used some totally different fungi from what either of its parent species use, then it might grow in a very different place,” says McCormick. “It might develop into a new species because it then would not have the opportunity to back-cross with either of the parents.”

Looking at patterns in the genomes can help researchers determine how recently the plants have begun to distinguish themselves as new species. In other words, the scientists are studying real-time evolution to better understand the genetic diversity of the orchids and how to restore them.

Orchids are rarely incorporated into landscape-restoration plans because of the complexity of their needs, says David Remucal, curator of endangered plants at the University of Minnesota. Remucal is leading an effort at the University’s Minnesota Landscape Arboretum to sample every orchid native to the state—a collection effort that shares plant matter and collaborates with the North American Orchid Conservation Center.

But, Remucal argues, with more knowledge that could change. He’s also leading an effort to incorporate the white lady’s slipper into a prairie restoration project on TNC’s Regal Meadow Preserve in Minnesota. No one is certain it will work the first time. Remucal wonders whether such recently replanted ground will have the necessary fungi to support the orchids. But it’s a start, he says.

At the same time, the particularity of orchids that makes them hard to restore also makes them a sign for conservationists like Landau that other restoration efforts are working—in her case at both Nassawango Creek and the undisclosed preserve in western Maryland.

On that spring day, while the team observed and documented the condition of the white lady’s slipper, Landau considered what its presence means for the landscape itself, and the years of work her team has put into protecting it.

“There’s so much that we don’t know,” Landau says. “But we know that when [orchids] show up, we’re doing something right. It’s almost whatever the opposite of a canary in the coal mine is. It shows us that we’re on the right track in a really pretty way.”

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Jenny Rogers is a writer and editor for Nature Conservancy magazine, covering books, science and conservation.


How to Identify Plants. Important Features of Flowering Plants

Flowering plants (Angiospermae) represent one of the largest groups of primary producers. Their contribution to the production of oxygen as well as that to the nutriment of animals and man is consequently very large. All features reviewed in this chapter refer to seed-producing plants, also called spermatophytes.

Typically, flowering plants are organized into an underground root and a shoot above ground that consists itself of a stem and leaves. The organs of a plant that serve sexual reproduction are the flowers. Part of the pollinated flower ripens and becomes the fruit.

In contrast to many other plant groups, flowering plants are striking, numerous and common. They are the most important group of the so-called primary producers that generate the prerequisite for life on earth: oxygen. Green plants have the ability to convert solar energy into chemical energy (photosynthesis) producing the oxygen necessary for all other organisms as a by-product. The useable plants among the flowering plants are - directly or indirectly - the basis of human existence they are, too, an important economical factor. A basic knowledge of flowering plants should therefore be among everybody's general knowledge.

Much has been written about flowering plants and every reader of this chapter will miss something that he regards worth knowing, while he might find other information trivial. But everybody will understand that it is impossible to review in a few lines a theme about which an extensive, partly popular scientific literature exists. And although this term may sometimes be used in a disparaging way, most of the popular scientific literature is scientifically correct, lucid and, above all, very well illustrated.

To get an idea of the variety of existing plants and to get to know special species, it is necessary to identify them. Many books on classification with different approaches exist. In many popular books, color photos or drawings are used and often is the color of the flower a primary feature of recognition. Most of the so-called scientific books on classification work on dichotomic keys, i.e. the user is asked a lot of questions in succession and has at each one to decide between two answers. This procedure is continued until the plant has been identified. The "scientific nature" is mostly based on the completeness of the varieties present in a book, since almost all of the illustrated books contain only the most common or most striking plants.

Recently, electronic tools have been used to figure out identification keys for plants. An example is the

The research into the flora of Central Europe has a tradition that goes back for centuries. It is mirrored in the nearly complete modern floras and books on classification. Incomplete, if existing at all, are books on the classification of less well discovered regions, like tropics, subtropics and many mountain areas.

The question of the origin of the wealth of forms (evolution) is discussed elsewhere where it is also shown that mountains with their rather small and isolated areas provide ideal conditions for the coming into being of new species. This is the reason, why even very experienced botanists equipped with renowned books on classification of the Central European flora will sometimes and in some places fail (Alps).

This chapter will deal with the characteristics of flowering plants that produce seed ( phanerogames or spermatophytes ) only. Many of the structures present in this plant group can be found with other non-flowering plants, too. But mosses, ferns and algae miss some features, like flowers or seeds while others, like roots or leaves exist in an incomplete way or are replaced by other organs.

The body of vegetation of many-celled algae (and mosses) is called thallus , that of flowering plants, ferns and fern-like plants (pteridophytes) is called cormus . The latter are therefore summed up as cormophytes. The special features of the different plant groups will be discussed later.

The body of vegetation of a "typical" flowering plant consists of an underground root and a shoot above ground. The shoot is organized into stem and leaves. Each of these basic organs can exist in many variations and these again can be combined in many different ways. The almost unlimited ability of combination is one of the main reasons of the existence of such a high number of species while at the same time, the identification of the relations of the species is aggravated.

If seemingly different organs with different functions can be traced back to the same basic organ, they are called homologous . It is also spoken of homology . Contrasting is analogy where organs with a similar look and function have descended from different organs.


The transfer of pollen from a male anther to a female stigma is called pollination. If male and female sex cells from the same species come together, fertilization takes place and seeds are made. Pollination occurs in various ways, such as by wind or by animals.

WHAT IS NECTAR?

Many flowers attract pollinating animals with a sweet, sugary liquid called nectar. If an animal feeds on the nectar, it picks up pollen and carries it to other flowers that it lands on.

WHAT IS WIND POLLINATION?

Pollination in some flowers occurs when pollen is blown from other flowers by the wind. Animal-pollinated flowers are strongly scented and brightly colored, but the flowers of wind-pollinated plants, such as grasses, are often small, with no petals.

FERTILIZATION

When a pollen grain lands on a stigma of the same species, it grows a tube into the ovule (seed-forming structure). A male sex cell travels down the pollen tube and fertilizes the ovum (female sex cell) to produce an embryo plant.


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Are flowers / flowering plants vital to all life on Earth? - Biology

Who knew!? According to a recent press release headline, plants apparently came from outer space and landed on Earth. at least if you believe a recent press release from University of Bristol about just published botanical research results by some of their researchers (February 19, 2018). If you then go on to read the research paper, you realize that the study they cite is really about LAND plants colonizing terrestrial areas, which sometimes are called earth, land, soil. any area above water. So this story is not about all plants, it is not about all of planet Earth it is about LAND PLANTS and TERRA FIRMA.

Screenshot of press release from University of Bristol, by BotanicalAccuracy.com (fair use).

This headline conjures up an image of some green plant aliens with seed and spore bomb landing on planet Earth 100 million years earlier than some unspecificed time.

Let's dig a little deeper in the press release.

INCORRECT. What is a plant? Is a plant just land plants? If so, then what are green algae? Again, what the authors mean here are land plants, not all plants. Land plants are green organisms that we find in terrestrial environments, from tiny mosses to giant Sequoias (not counting some terrestrial green algae). Some green algae (streptophytes) are more closely related to land plants than to other green algae (chlorophytes, yes, biological reality is complicated).

The ancestors to land plants were ancient green algae from the streptophyte group, and green algae still live mostly in aquatic environments, both in seawater and freshwater. If you agree that we should classify life on Earth in groups that reflect their evolutionary relationships, then organisms from the red algae + green algae + land plants form a solid, good group for classification, simply called the Plants or Plantae (see the evolutionary tree below).

How plants have evolved. a little simplified, but rather scientifically correct.
by Maulucioni - Own work, CC BY-SA 4.0, Source
However, an alternative explanation to this mistake in this press release is that the writers of this press release still followed the old 5-kingdom classification of life. This system has been shown over and over to not be correct evolutionarily, and therefore has been abandoned by modern researchers and taxonomists. The earlier system included ANIMALS, FUNGI, PLANTS, ALGAE, PROTISTS for the eukaryotes - and the Algae group has been shown to be a messy grab-bag of unrelated groups. If this is what happened, then it is time for a knowledge update for these scientists and the public - new information is always interesting and fun and fascinating, and science is about progress and increased knowledge and changes based on new data, so there is no excuse to hold on to old hypotheses and systems.
Teaching the public about new taxonomic results and changes, including the difference (and similarites) between the closely related fungi and animals, or, explaining that the old groups 'Protists' and 'Algae' are a mish-mash grab bag of unrelated organisms that should not be classified together, is what scientists and journalist should do - it should be part of our job descriptions and job expectations. There is no need and no excuse to hold on to outdated information if you care about scientific accuracy. There is also no way we as individuals can keep ourselves updated on all new information that is coming out of science on a daily basis that is why we turn to experts for fact checking and updates. Change, corrections, and updates should be welcome in science, and it is part of the scientific process and its progress.

WELL. So, what are the oldest plant fossils? Again, that depends on your definition of plants. The oldest land plant fossils are about 420 million years old, but there are possible red algae fossils from 1.6 billion years ago and also from 1.2 billion years ago. There are plenty of additional algal fossils from more than 500 years ago. So, again, speaking about land plants, versus plants, make a big difference.

CORRECT, BUT. (note how the land plants finally enter the story). Ancestors, evolutionary speaking, is not just one organism at one time. Ancestors and their extinct species and populations are lining up as a string of organismal pearls back into the distant, forgotten past. And if we continue to follow the ancestral lineages back in time for plants, it ends up at the common ancestor of all living things, common to bacteria to humans, to wolves, sea cucumbers and molds, and for magnolias and mosses and moths. The common ancestor for land plants only, that is different, that is the ancestral (and extinct) organism that is the closest ancestor to the now living land plants.

HOW TO FIX? To fix the problems in this press release would be really easy, and here is my suggestion (new or changed words in red and bold):

It would also have been nice if scientific names would have been italicized in the press release, as is custom in biology. (See this previous blog post)

WHY CARE? When science is communicated to the public, it is not only important that it is correct, but also that it is understandable by a broad audience. Clearly defined words and simplicity is necessary, but it absolutely needs to be correct. Otherwise it turns into botanical fake news that mislead the public and upset scientists. To assume that people only think about land plants when you use the word 'plants' assumes that the public does not know about green algae in oceans or in lakes, you ignore current scientific data, and it also shows that you as a scientist or journalist do not care about the details that build the real story.

As scientists, we often get frustrated when there are factual inaccuracies in how our research results and scientific facts are portrayed by non-scientists. In this case though, it was the home institution of the research team that introduced these mistakes and inaccuracies in their own press release, and then, assuming it was of course correct, it was picked up by news media. This is highly unusual. More often it is a journalist without much scientific knowledge that introduces errors or simplifies too much from a press release that was accurate to begin with.


Sometimes seemingly simple omissions (plants / land plants) and capitalization (Earth / earth) really makes a big difference, as shown in this story. ScienceDaily picked up the story from the press release as is, as did Phys.org, Sci-News, Astrobiology Magazine. But look at BBC, and Atlas Obscura, and Science Magazine - they use the wording 'land plants' and have accurate information in their articles that were not direct copies of the press release. Kudos to them!

Note. One person at the University of Bristol was contacted before this story was written and published on BotanicalAccuracy.com, and this person declined to reconsider word choices or make suggested corrections in the press release.

It is also important to note that the issues highlighted in this blog post are only present in the press release from University of Bristol, not in the research paper itself, nor in the quotes from the scientists in the press release. So it is the dissemination of the research results that is the problematic issue here, not the research itself.

For more reading on plants and algae, I recommend this recent blogpost:
Are algae plants? from the In Defense of Plants blog


Why Hasn’t This Happened in Other Plants?

If having more veins and stomata is so helpful, why hasn’t this evolved in other plants? Well, in truth, it’s because all of these structures are made up of cells. If you want more transport methods in a leaf, you need more cells to make them, but that would mean a bigger leaf, which would need even more veins and stomata - see the issue here? It’s a cycle that would usually create bigger plants, unless of course, you find a way to make smaller cells. Angiosperms have small cells that can make a dense network of veins and stomata, like a bunch of side-by-side subway routes! So the next question is, how do you get smaller cells?

This image shows the amount of space a nucleus (and the DNA within) can take up in a cell. Click for more detail.

You might picture DNA as a tiny little chain, but when you are working within tiny, tiny cells, that DNA can take up a lot of space. The entire code of DNA (an organism’s whole genome) is in almost every one of that organism’s tiny cells. If there was a way to get rid of a bunch of DNA, you can have smaller cells. Smaller cells can leave room for more veins between cells, and for more specialized cell structures, like stomata.

The scientists came to this idea by looking at the genomes of a bunch of plant species (not just angiosperms). They measured which plant species had the smallest genomes and therefore, the least amount of DNA in each cell. Thankfully, they didn’t need to do all these measurements themselves. A lot of information on plant DNA has already been recorded.


Cultural Importance of Pollination

Native Peoples traditionally recognized the importance of pollinators:

We explore only a few examples of culturally important pollinators or pollinated plants here. To learn more about culturally important plants and pollinators:

  • “Ethnobotany” is the study of how people of a particular culture and region make use of indigenous (native) plants. Since their earliest origins, humans have depended on plants for their primary needs and existence. Plants provide food, medicine, shelter, dyes, fibers, oils,resins, gums, soaps, waxes, latex, tannins, and even contribute to the air we breathe. Many native peoples also used plants in ceremonial or spiritual rituals. Examining human life on earth requires understanding the role of plants in historical and current day cultures. Read more about Ethnobotany&hellip - a Natural Resources Conservation Service Plant Material Program presentation.

Cultural Symbolism

Butterflies

  • Raven&rsquos spokesperson - Haida (Pacific NW)
  • Messenger (in dreams) from Great Spirit - Blackfoot
  • Earth&rsquos fertility - Hopi &ldquoBulitikibi&rdquo harvest dance
  • Flame, Teotihuacan (Palace of the Butterfly) - Ancient Mexicans (Olmecs, Toltecs, later Aztecs)
  • Ancestor - Sumatra, Naga (Madagascar), Pima (N. America)
  • Related to Morning Star - Arapaho, Mexecal

Moths

  • &lsquoTun tawu = &ldquogoes in and out of fire&rdquo - Cherokee (North America)
  • Symbol of knowledge, guardians of gold dust of eternity - Yaqui (Mexico)
  • Powder - insanity (moth-crazy, sexual excess, incest, aphrodisiac) - Navajo (North America)
  • Guardian of tobacco (caterpillar of Sphinx moth) &ndash Navajo (North America)

Hummingbirds

  • Basket weaving teacher - Taroscan (Mexico)
  • Courier of gifts to Great Mother - Pueblo Indian Tribe
  • Convinced gods to bring rain &ndash Hopi and Zuni Indian Tribes
  • Sun in disguise (courting the moon) - Maya

"Ethnobotany&hellipplants sustaining people" Poster PDF Version, 2.6 MB

A hummingbird flits among the blossoms of a fireweed. This original design was done in the style of, and greatly influenced by, the delicate form, lines, and art of the Tsimshian and Tlingit peoples of southeast Alaska. Photo courtesy of Julie Thompson, Featherlady Studio.



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