Tag: Vision

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Flickerings by John Hawkhead

migraine flickerings
sighting an electron stream
leave free radicals

by John Hawkhead

A free radical is an atom, ion or molecule with at least one unpaired valence electron and which are usually highly chemically reactive with short lifetimes.

They are formed either from other radicals or by breaking a covalent bond in a spin-paired molecule, leaving each of the fragments with one of the electrons in the original bond.

The author of this haiku suffers from migraines where vision is impaired in such a way that there appears to be a stream of electrical waves and particles across the eye.

Further reading:

‘Radical (Chemistry)’, Wikipedia article: https://en.wikipedia.org/wiki/Radical_(chemistry)

‘Migraine’, Wikipedia article: https://en.wikipedia.org/wiki/Migraine

Author bio:

John Hawkhead (@HawkheadJohn) has been writing haiku and illustrating for over 25 years. His work has been published all over the world and he has won a number of haiku competitions. John’s books of haiku and senryu, ‘Small Shadows’ and ‘Bone Moon’, are now available from Alba Publishing (http://www.albapublishing.com/). Read more of John’s sciku here!

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Backlit Billboards in the Sea by Prof Teena Carroll

Sending messages,

luminescent Humboldt Squid

flicker in the deep.

by Teena Carroll

A group of scientists at the Monterey Bay Aquarium Research Institute conducted a study of Humboldt squid using remote operated vehicles.  They wanted to determine how a group of squid could execute complex behaviors in low light deep sea conditions.  For instance, the squid avoid body contact with each other even when pursuing the same prey.

Burford and Robison (2020) found that the squid used specific color patterns on their bodies primarily when they were hunting in groups.  Normally, such color changes would not be visible in the deep sea; Humboldt squid are bioluminescent which researchers hypothesize essentially provides backlighting to highlight the color changes.

The complexity of the color changes prevented the researchers from translating exactly what the squid are communicating.  However they were able to document that the patterns are a consistent and effective communication method.  After observing repeated patterns, they think that the visual language of the squid may be evolved enough to use syntax.

Original research: https://doi.org/10.1073/pnas.1920875117

Additional information: https://www.mbari.org/humboldt-squid-signaling/

Teena Carroll is a mathematics professor at Emory & Henry College in Southwest Virginia and has been a poet longer than she has been a mathematician. @Teena Carroll

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Exploiting blind spots

Tropical clawed frogs –

what you can’t see can’t hurt you.

Exploiting blind spots.

 

Providing sufficient shelter for animals in captivity is frequently an important method to improve welfare, however cover may limit the ability to observe animals for health checks. Western clawed frogs (or tropical clawed frogs) are a common model organism, kept in high numbers in laboratories around the world, but there is comparatively little empirical evidence for how best to adequately house this species in captivity.

Cooke (2017) found that a black overhead cover was the optimal method of providing refuge for this species. In a second experiment exploiting the frog’s inability to see certain wavelengths the black cover was swapped for a red translucent cover which was found to be just as effective.

Red translucent covers could therefore be an effective method of providing refuge for the animals whilst simultaneously allowing carers to observe and conduct health checks.

Original research: https://doi.org/10.1177/0023677217737798

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Little peepers

Nocturnal Kiwi.

Redundant little peepers –

can survive blindness.

 

Most birds have excellent vision, even those that are active under low light conditions. In contrast the kiwi has the smallest eyes relative to body mass of any bird and poor vision. In fact, kiwis have been observed surviving in good condition in the wild despite being completely blind (Moore et al, 2017). Kiwis instead have sensitive auditory, olfactory and tactile somatosensory systems which they use to navigate the world and survive.

Original research: https://doi.org/10.1186/s12915-017-0424-0

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Fight, flight or pee

To fight, flight or pee?

That is the question for the

Aggressive cichlid.

 

Aggressive interactions between individuals can be dangerous and energetically expensive and it is important that the two competitors are able to communicate effectively to avoid such costs. When competing cichlid fish engage in agonistic interactions they are known to communicate via visual cues, but new findings suggest they also use chemical cues by urinating during encounters. Bayani et al, 2017.