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ABOMINABLE MYSTERY. "Darwin called their sudden appearance in the fossil record an “abominable mystery.” Since Darwin's time, we have been able to clarify that picture a little bit. Even so, our understanding of the origin of the angiosperm lineage is dubious at best. When and why did flowers evolve? There is scant fossil evidence to illustrate the early evolutionary steps in this development of flowers." https://lnkd.in/euP3eDr View in LinkedIn

INITIATED BY DARWIN. "In his book entitled The Power of Movement in Plants, Darwin (1880) described many examples of “sleep movements of leaves” and provided a “List of Genera, including species the leaves of which sleep”. Among these, he noted that the legume family “includes many more genera with sleeping species than all the other families put together.” He also described a specialized organ, called a joint, cushion, or pulvinus responsible for such movement. https://lnkd.in/eE__XBs View in LinkedIn

"FLOWER OPENING depends on petal movements, of which at least four types can be distinguished. (1) Opening is due to reversible ion accumulation, and independent of elongation growth; (2) it depends on cellular death in a specific area of the petal; (3) it is due to loss of water during the day and refilling during the night; and (4) it depends on differential growth." https://lnkd.in/eTEzGE9 View in LinkedIn

ELEGANT ENGINEERING. "In some flowers, for example in Oenothera spp., the sepals are connected by a zipper‐like mechanism whereby cells at the sepal margins are tangled. Due to the force of the growing petals this entanglement is broken and the petals are suddenly released. In several other species the sepal margins are tightly held together by ridges, which also delay opening until the growing petals overcome their resistance. This also results in rapid opening." https://lnkd.in/eTEzGE9 View in LinkedIn

DIVERGENT SOLUTIONS. "Depending on the species, opening may relate to the development of tissues adjacent to the flower, for example, opening may require growth of the pedicel, as in several species in the Iridaceae; or it may require forced separation or abscission of covering parts, such as bracts or sepals." https://lnkd.in/eTEzGE9 View in LinkedIn

FOLDING ORIGAMI is not the simplest of projects, especially if the folding parts get damaged by weather or predators. Folding and unfolding of flowers is a complex and biologically costly venture. It is surprising that nature has elected to fold and unfold such seemingly delicate structures as flowers so frequently. View in LinkedIn

SWIFT AND COMPLEX. "Flower opening is often rapid. In Oenothera biennis, for example, full opening takes less than 20 min and in Hedera helix it occurs in about 5 min. Flower opening is therefore interesting from a physiological point of view as, in many species, it is accompanied by a high rate of cell expansion, rather impressive movements, and complex regulation by external and internal factors." https://lnkd.in/eTEzGE9 View in LinkedIn

RESPONSIVENESS. "Plants respond to light, gravity, touch, and other environmental signals by both temporary and permanent differential growth. Certain plant species respond to light, dark, and other environmental factors by leaf movement. Leguminous plants both track and avoid the sun through turgor changes of the pulvinus tissue at the base of leaves. Mechanisms leading to pulvinar turgor flux." https://lnkd.in/e9s_fPH View in LinkedIn

NYCTINASTY. "Tropisms are plant movements induced by directional stimuli, such as light or gravity. In addition, plants can move in response to nondirectional factors, such as humidity or contact. These movements are called nastic responses. Nyctinasty, the proper name for the “sleep movements of leaves” is a well-known example of a nastic response. In this case, plants close up their leaves and petals in response to the onset of darkness. Because it is a rather fast response, it does not involve differential growth but changes in cellular turgor." https://lnkd.in/eE__XBs View in LinkedIn

EPIGENETICS NUANCES GENETIC SYNTAX. "The interesting thing is that the variety of parts that constitute the phenotype throughout its developmental stages as well as its regulation is coded in the genotype together with epigenetic markings. Epigenetics is an effective tool for expanding the informational content of a given nucleotide sequence syntax with multiple meanings/functions." https://lnkd.in/eg6uePF View in LinkedIn