Plants

We’ve been talking about intelligence in termite mounds. Not “of” termite mounds but “in” them. From a review of The Revolutionary Genius of Plants: A New Understanding of Plant Intelligence and Behavior, by plant biologist Stefan Mancuso, To overcome the human bias toward brain-centered intelligence, Mancuso writes, one must consider that, unlike animals, plants can’t move. Being anchored in one spot required that plants evolve entirely different solutions to short- and long-term threats like predators, fire and drought. (Animals do not solve problems, notes Mancuso, they avoid them.) The plant solution is decentralization: Rather than having a brain, kidneys or other organs that would be points of vulnerability, plants are modular. Functions that would be carried out by organs in an Read More ›

From ScienceDaily: In one video, you can see a hungry caterpillar, first working around a leaf’s edges, approaching the base of the leaf and, with one last bite, severing it from the rest of the plant. Within seconds, a blaze of fluorescent light washes over the other leaves, a signal that they should prepare for future attacks by the caterpillar or its kin. That fluorescent light tracks calcium as it zips across the plant’s tissues, providing an electrical and chemical signal of a threat. In more than a dozen videos like this, University of Wisconsin-Madison Professor of Botany Simon Gilroy and his lab reveal how glutamate — an abundant neurotransmitter in animals — activates this wave of calcium when the Read More ›

Plants are thought to have started moving to land 500 million years ago. The algae are presumed to have been carrying the redundant genes since then. So did they then pre-exist the move to land? From ScienceDaily: 500 million years ago, the first plants living in water took to land. The genetic adaptations associated with this transition can already be recognized in the genome of Chara braunii, a species of freshwater algae. An international research team headed by Marburg biologist Stefan Rensing reports on this in the journal Cell. Rainer Hedrich and Dirk Becker from Julius-Maximilians-Universität Würzburg (JMU) in Bavaria, Germany, are also members of this team. “The genes of the Chara braunii alga comprises numerous evolutionary innovations that have Read More ›

With an interesting chapter on carnivorous plants. At Oscillations, Suzan Mazur takes note of the new book by structuralist Antonio Lima de Faria, now an emeritus professor at Lund University, whom she describes as “one of the Osaka Group of ‘structuralists,’ whose other members included Brian Goodwin, Mae-Wan Ho, Peter Saunders et al.” The main theme of Periodic Tables Unifying Living Organisms at the Molecular Level: The Predictive Power of the Law of Periodicity is that “the recurrence of form and function in biology makes possible a periodic table similar to the periodic table of chemical elements (a subject first explored in his 1983 book) and reveals the “law of biological periodicity.” Carnivorous plants have long been an evolutionary puzzle: In the section “Periodicity of Plant Carnivory,” Lima-de-Faria makes Read More ›

From at ScienceDaily: Self-fertilization is a problem, as it leads to inbreeding. Recognition systems that prevent self-fertilization have evolved to ensure that a plant mates only with a genetically different plant and not with itself. The recognition systems underlying self-incompatibility are found all around us in nature, and can be found in at least 100 plant families and 40% of species. … In plants such as snapdragons and Petunia, when the pollen lands on the stigma, it germinates and starts growing. The stigma, however, contains a toxin (an SRNase) that stops pollen growth. Pollen in turn has a team of genes (F-box genes) that produce antidotes to all toxins except for the toxin produced by the “self” stigma. Therefore, pollen Read More ›

From ScienceDaily: Scientists at Washington State University and China Jiliang University have discovered that the quality of the host rice plant determines whether the brown planthopper, a major pest on rice in Asia, grows short wings or long wings. Wing size determines whether the insect can fly long distances to other plants or stick around and feed off nearby rice plants, said Laura Lavine, professor in WSU’s Department of Entomology. “It’s all about the amount of glucose, or sugar, in the plant,” Lavine said. “Rice plants with higher glucose levels are older and dying. That increase in glucose causes adolescent brown planthoppers to develop into the long-winged adults. The plant really is telling the insect how to grow.” … “It’s Read More ›

From Gerd Bossinger and Antanas Spokevicius at Phys.org: From ancient European beech trees to gigantic Californian redwoods and Australian mountain ashes, new research has found the enormous trunks of these trees are all formed from a single layer of cells no wider than the tip of a needle. … Wood is one of the world’s most important renewable resources, so you’d think we’d have an understanding of how it grows. But until now we didn’t know exactly how cells within the vascular cambium go about their business. The number of cell layers that make up the vascular cambium, and to what degree the fate of individual cells within the cambium is predetermined, has been a matter of debate for over Read More ›

From Haley Dunning at Imperial College of London: The vast majority of life on Earth uses visible red light in the process of photosynthesis, but the new type uses near-infrared light instead. It was detected in a wide range of cyanobacteria (blue-green algae) when they grow in near-infrared light, found in shaded conditions like bacterial mats in Yellowstone and in beach rock in Australia. As scientists have now discovered, it also occurs in a cupboard fitted with infrared LEDs in Imperial College London. … The standard, near-universal type of photosynthesis uses the green pigment, chlorophyll-a, both to collect light and use its energy to make useful biochemicals and oxygen. The way chlorophyll-a absorbs light means only the energy from red Read More ›

From Bill Andrews at Discover: In particular, according to a study released Monday in Nature Chemistry, an international team of scientists showed that molecules involved in photosynthesis display quantum mechanical behavior. Even though we’d suspected as much before, this is the first time we’ve seen quantum effects in living systems. … With a technique called two-dimensional electronic spectroscopy, researchers saw molecules in simultaneous excited states — quantum weirdness akin to a cat being alive and dead at the same time. What’s more, the effect lasted exactly as long as theories predicted it, suggesting this evidence of quantum biology will last. As the authors succinctly put it, “Thus, our measurements provide an unambiguous experimental observation of excited-state vibronic coherence in the Read More ›

From Douglas E. Soltis, Michael J. Moore, Emily B. Sessa, Stephen A. Smith, and Pamela S. Soltis, Using and navigating the plant tree of life, at Amerian Journal of Botany 7 April 2018 https://doi.org/10.1002/ajb2.1071 (open access) : The “tree of life” has become a metaphor for the interconnectivity and breadth of all life on Earth. It also has come to symbolize the broad investigation of biodiversity, including both the reconstruction of phylogeny and the numerous downstream analyses that are possible with a firm phylogenetic underpinning. … Accompanying these exciting advances are equally significant challenges that remain for the construction of a better and more complete picture of the evolution of plant lineages. In addition to the computational challenges of larger Read More ›

From ScienceDaily: Queensland University of Technology (QUT) researcher Dr Robyn Araujo has developed new mathematics to solve a longstanding mystery of how the incredibly complex biological networks within cells can adapt and reset themselves after exposure to a new stimulus. … “Proteins form unfathomably complex networks of chemical reactions that allow cells to communicate and to ‘think’ — essentially giving the cell a ‘cognitive’ ability, or a ‘brain’,” she said. “It has been a longstanding mystery in science how this cellular ‘brain’ works. “We could never hope to measure the full complexity of cellular networks — the networks are simply too large and interconnected and their component proteins are too variable. “But mathematics provides a tool that allows us to Read More ›

From Dan Garisto at Science News: New genetic evidence instead suggests that wild precursors to sweet potatoes reached Polynesia at least 100,000 years ago — long before humans inhabited the South Pacific islands, researchers report April 12 in Current Biology. If true, it could also challenge the idea that Polynesian seafarers reached the Americas around the 12th century. … The researchers calculated the average rate of genetic change for the plant, determining that the Polynesian sweet potato diverged from its South American cousin at least 100,000 years ago. That suggests the plants, or their seeds, somehow migrated across the ocean on their own, possibly via wind, water or birds. Precedent exists, the authors note. Two other Ipomoea species crossed the Read More ›

From at ScienceDaily: Ancient microbes may have been producing oxygen through photosynthesis a billion years earlier than we thought, which means oxygen was available for living organisms very close to the origin of life on earth. In a new article in Heliyon, a researcher from Imperial College London studied the molecular machines responsible for photosynthesis and found the process may have evolved as long as 3.6 billion years ago. … One surprising finding was that the evolution of the photosystem was not linear. Photosystems are known to evolve very slowly — they have done so since cyanobacteria appeared at least 2.4 billion years ago. But when Dr. Cardona used that slow rate of evolution to calculate the origin of photosynthesis, Read More ›

Earth’s history, our planet’s continents would have been devoid of all life except microbes. All of this changed with the origin of land plants from their pond scum relatives, greening the continents and creating habitats that animals would later invade. The timing of this episode has previously relied on the oldest fossil plants which are about 420 million years old. New research, published today in the journal Proceedings of the National Academy of Sciences, indicates that these events actually occurred a hundred million years earlier, changing perceptions of the evolution of the Earth’s biosphere. The researchers were using molecular clock technology. Co-lead author Mark Puttick described the team’s approach to produce the timescale. He said: “The fossil record is too Read More ›