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Topics about "vascular bundles" include:

  1. Secondary xylem (wood) in vascular plants
    Evolution of wood in plants as distantly related as lignophytes, Calamites and Lepidodendron is an elegant example of convergent evolution. Plants responded in a similar way to a need for better structural support as they diversified and increased in size.

  2. Xylem vessels in vascular plants
    Vessels are characteristic of the angiosperms, and yet they have evolved independently in several other groups, including the lycophyte Selaginella, horse-tail Equisetum and the enigmatic Gnetales.

  3. Torus-margo pits in vascular plant xylem
    Torus-margo pits probably evolved once in the gymnosperms, after the split of more advanced gymnosperms from the cycads. Surprisingly, eight genera from five families of angiosperms, which are characterised by highly effective xylem vessels, have also evolved torus-margo structures.

Topics containing the search term "vascular bundles" are:

  1. Hearts in cephalopods and vertebrates
    There is a striking convergence between the aorta of the cephalopod and vertebrate heart, notably in its structure and the employment of elastic proteins.

  2. Secondary xylem (wood) in vascular plants
    Evolution of wood in plants as distantly related as lignophytes, Calamites and Lepidodendron is an elegant example of convergent evolution. Plants responded in a similar way to a need for better structural support as they diversified and increased in size.

  3. Agriculture in gall midges (Diptera)
    Flies, fungi, farming - sounds interesting? Read on if you want to learn about some rather different gall midges...

  4. Desert plants with succulent stems
    Fleshy, succulent stems have evolved in several distantly related desert plant families, including cacti, certain species of Euphorbia and two genera of the family Asclepiadaceae, Hoodia and Stapelia.

  5. Torus-margo pits in vascular plant xylem
    Torus-margo pits probably evolved once in the gymnosperms, after the split of more advanced gymnosperms from the cycads. Surprisingly, eight genera from five families of angiosperms, which are characterised by highly effective xylem vessels, have also evolved torus-margo structures.

  6. Succulent desert plants
    Classic examples of convergence in desert plants include the so-called 'stem succulent' cacti in the Americas and cactus-like Euphorbia species in Africa and South Asia, and also the striking similarity between 'leaf succulent' Agave and Yucca of the Americas and Aloe and its close relatives in Africa.

  7. Reversion from xylem vessels to tracheids
    In three plant taxa that evolved in environments with frequent freeze-thaw cycles (Winteraceae, Trochodendraceae and cold desert Ephedra), vessel evolution has been reversed independently in favour of a return to a tracheid-based vascular system.

  8. Xylem vessels in vascular plants
    Vessels are characteristic of the angiosperms, and yet they have evolved independently in several other groups, including the lycophyte Selaginella, horse-tail Equisetum and the enigmatic Gnetales.

  9. Infrared detection in animals
    Some snakes are famous for 'seeing' infrared, but did you know that their heat-sensing abilities are rivalled by some beetles that can detect forest fires over considerable distances?

  10. Mammal-like placentation in skinks (and fish)
    “Only two types of vertebrates [have] evolved a reproductive pattern in which the chorioallantoic placenta provides the nutrients for fetal development. One is [...] the eutherian mammals […], and the other, a few lineages of the family Scincidae.” A.F. Flemming (2003) J Exp Zool 299A 33-47

  11. Vision in echinoderms
    Among brittlestars and sea urchins we find visual systems that in some ways rival the arthropods in the form of compound eye-like structures.

  12. Infrared detection in snakes
    Warm-blooded rodents watch out! There are heat-sensing predators on the prowl...