HOW DO BEES (AND HUMANS) SEE GREY LEVELS?

HOW DO BEES (AND HUMANS) SEE GREY LEVELS?

Adrian Horridge

15,23 €
IVA incluido
Disponible
Editorial:
Peacock Press
Año de edición:
2023
ISBN:
9781914934544
15,23 €
IVA incluido
Disponible
Añadir a favoritos

There are several sources of serious confusion in the investigations of how bees and humans see grey and black. First, von Frisch trained bees to go to a coloured paper, and then tested whether they could distinguish that colour from a palette of 15 shades of grey placed together on a test board. Unfortunately, he used papers made from wood pulp, which do not reflect ultraviolet, so the UV receptors were excluded. Secondly,16 years later it was shown that bees require a 25% difference in brightness to discriminate grey levels, so his test was uncertain. Thirdly, bees are dichromats, and detect only green contrast and the fraction of light that stimulates the blue receptors. The most interesting confusion is that grey photons do not exist, but that does not affect bees because they are functional dichromats and treat grey like any other colour. No problem. The UV receptors in the compound eyes of the bee are used to detect the direction of the sky to stabilize flight and escape upwards when disturbed. The bee is a sexless herbivore, which may account for its relatively simple retina. Additional colour types of receptor have been found by recording from eyes of some flies, butterflies and dragonflies, presumably for unique recognition of the other sex or prey. However, this is one-purpose vision which does not require much processing or large brain. Full colour vision requires at least three colour types of receptors and a large visual cortex, as in primates.Human vision is more difficult to understand in this context. Black is entirely a hallucination because there are no black photons. White is detected normally with three receptor types acting together, but the brightest objects in sight also look white even though they are green or red, maybe as a calibration. The edges of shiny objects also look white although clearly they are not. Grey is hallucinated as various levels of black where there is white but insufficient illumination to see it as white.These topics are discussed in historical context. However, some who work on the vision of the bee still believe that bees have full colour vision, and many believe that their dog or cat sees only black and white, so called achromatic vision. However, like the bee, they all evolved in world where green predominated, and many things of interest were less blue (e.g., yellow) or more blue than green (e.g., blue), so most mammals evolved as dichromats, without UV or red receptors. 

Artículos relacionados

  • MODE-LOCKED LASERS
    NILOY K DUTTA
    This invaluable book provides a comprehensive treatment of the design and application of Mode Locked Lasers and Short Pulse Generation. With the advances in semiconductor laser and fiber laser technologies in the 1980s to now, these devices have been made compact, refined, and developed for a wide range of applications including further scientific studies.Semiconductor mode-loc...
    Disponible

    157,19 €

  • Compact Sources of Ultrashort Pulses
    ...
    Disponible

    244,00 €

  • Northern Lights
    V T SREEKUMAR
    Northern Lights: A Journey through Science and SplendorDiscover the magic and mystery of the Northern Lights in 'Northern Lights: A Journey through Science and Splendor.' This captivating book takes you on an enlightening expedition into the heart of one of nature’s most awe-inspiring phenomena-the Aurora Borealis.Delve into the scientific marvels behind the Northern Lights as ...
    Disponible

    33,90 €

  • Manual of Spectroscopy
    Theodore A. Cutting / Theodore ACutting
    CONTENTS - Preface - I. History and Theory of Spectroscopy - 1. Historical Review - 2. The Atom in Spectroscopy - II. Light Sources - 1. The Electric Arc - 2. The Spark - III. Spectroscopes - 1. Optical Systems - 2. Industrial Spectrographs - 3. Spectroscope Construction - IV. Spectroscopic Analysis - 1. Qualitative Analysis - 2. Determinations - 3. Quantitative Analysis - V. T...
    Disponible

    64,67 €

  • Chevreul on the Laws of Contrast of Colour
    Michel Eugène Chevreul / John Spanton
    Discover Michel Eugéne Chevreul’s groundbreaking theories on colour as he explores the principles of contrasting and harmonising colours in this classic text on colour theory.First published in 1839 as De la Loi du Contraste Simultané Des Couleurs Atlas, Chevreul’s work followed that of Isaac Newton and Johann Goethe. His comprehensive colour guide introduces the concept of si...
    Disponible

    39,22 €

  • Visionary Lenses
    V T HARIKUMAR
    'Visionary Lenses: How Optical Components Shape Our World' offers a comprehensive exploration of the remarkable influence that lenses and optical components have had on human progress and understanding. This book delves deep into the science of optics, tracing the evolution of lens technology from its earliest origins to the cutting-edge innovations that drive modern advancemen...
    Disponible

    30,99 €

Otros libros del autor

  • Vision of the Honeybee Mimic
    Adrian Horridge
    Among the fly family Syrphidae are many examples of bee mimics, mostly of the genus Eristalis, among which we found the world-wide common dronefly, Eristalis tenax, most convenient for detailed study, as there is no sting. As would be expected for a fly, the eye is much larger than that of the honeybee.Our analysis revealed it as a typical fly visual system with some specialise...
    Disponible

    13,04 €

  • How Flying Bees Pilot, and other arthropod wonders
    Adrian Horridge
    After publishing, with Ted Bullock, the two-volume work on Invertebrate Neurobiology, in 1962 Adrian selected a new topic, and built up a group at St Andrews (and later at the Australian National University), specializing in the optics, neuron anatomy and electrophysiology of the arthropod compound eye, which offered a wide variety of topics.Neuron anatomy of insect visual syst...
    Disponible

    15,88 €

  • Honeybees Vision
    Adrian Horridge
    Professor Adrian Horridge has thoroughly enjoyed a long and productive career in scientific research. At 17 he won a scholarship to St John’s College Cambridge, where he spent 10 years, from student to a fellowship, ending in the Zoology Department working with new techniques of recording from nerve cells. Some of this time was spent at the Naples Marine Laboratory and at the D...
    Disponible

    15,23 €