Seeing in the Dark and the Green: How Eyes and Leaves Share a Lighty Secret

The world of biology reveals surprising connections, and the human eye and a seemingly ordinary leaf share a fascinating one. Both organs rely on sophisticated light-sensing mechanisms to function effectively in their environments, despite their vastly different purposes.

Within the human eye, the retina houses two crucial photoreceptor cell types: rods and cones. Rods, responsible for low-light vision, utilize rhodopsin, a specialized protein, to capture even the faintest light signals. Cones, responsible for color vision, rely on various forms of iodopsin to differentiate colors in bright light conditions. Both rhodopsin and iodopsin function by undergoing a shape change upon encountering light, triggering a biochemical cascade that ultimately translates light energy into electrical signals the brain interprets as vision.

Plants exhibit a similar strategy. Nestled within their leaves lies phytochrome, a remarkable molecule that, like its counterparts in the eye, acts as a light receptor. Phytochrome exists in several states depending on the specific wavelengths of light it absorbs. By sensing variations in light intensity and spectrum, phytochrome provides the plant with vital information about its surrounding environment. This information plays a critical role in processes like photosynthesis, where plants utilize sunlight as an energy source, and regulates growth patterns based on light availability.

In both the eye and the plant, the photosensors function together with chromophores: retinal in the eye and phytochromobilin in the plant.

This unexpected parallel between the human eye and the leaf underscores a fundamental principle in biology – the ability to detect light is a powerful evolutionary advantage. By harnessing the power of light, both humans and plants gain the ability to navigate their environments, grow, and thrive.

A final prayer whispered as darkness consumes.

(I don't really feed my snake live prey)

When I discover something...😅

Tiny leopard slugs (Limax maximus) everywhere! 🥰 They are totally cute as babies and popular in gardens because they fatally attack other slugs.☠️

Dobby is a good boy! 🐶💛

This bug knows how to get through life.✌️😎

Brown marmorated stink bug (Halyomorpha halys) trapped by a garden spider (Araneus diadematus).

🐞🌿 A ladybug nymph fell on my hand and clung to it tightly. 😅🤷‍♂️ I let it climb into a bush. Baby saved! 🤗

Green shield bug,
Palomena prasina
(07/2021 in Oberursel)


Little stinker in its fourth instar. Two moults remain until adulthood. It's a very common European species. You can find them from North Africa across Europe to Central Asia. It prefers to live on deciduous trees (linden, alder), bushes, nettles and thistles. I found this one below a linden tree. In German we call them Grüne Stinkwanze (green stink bug). My friends from North America have a very similar bug with that name (Chinavia hilaris). But they differ much in color in their larval stage and have a few small differences as adults. Both species are member of the Pentatomidae family, generally called shield bugs or stink bugs. They have in common that they release a pungent defensive spray when threatened, disturbed or crrrrushhhhed.💚

Common darter (male),
Sympetrum striolatum
(09/2020 in Turnhout, Belgium)

Firebug nymph,
Pyrrhocoris apterus
(08/2020 in Oberursel, Germany)

My buddy C-7 (Coccinella septempunctata) 🐞🌞

Just a bark-eating zophoba beetle. In addition to isopods and springtails, they take care of the cleanliness of my corn snake terrarium. They cope better with the conditions in the terrarium than isopods and springtails. In the nature of their Central and South American homeland, they feed on guano from fruit-eating bats. In my terrarium they eat undiscovered remains of my snake. However, you should make sure that the zophobas don't take over. They could become a stress factor and life risk for the main residents. The larvae also like to eat styrofoam, from which many back walls are made. They eat almost everything! That's why it's important to keep an eye on it. Since zophobas pupate only in isolation, there is only a small risk of overpopulation (depending on the interior). Also, the larvae from the terrarium shouldn't be fed to other animals because this could spread diseases. If you notice that they become too many, you can put wet pieces of bark in the terrarium. An hour later you collect the bark together with the larvae and kill them friendly in the freezer. The easiest way is to collect the adult beetles and allow only a few to lay eggs. Because of these peculiarities, I cannot fully recommend it, but I have had good experiences myself. We're all pioneers with different experiences.