Ins & Outs of Fluid balance in Desert Animals (Part 1)

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Maintaining their hydration is a major problem for desert animals. Large mammals e.g. Gemsbok & small mammals e.g. rodents use different strategies to cope with arid conditions. We will discuss the special behavioral or physiological adaptations that have evolved in … Continue reading

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Uncoupled heating: Warthogs lack brown fat & live in burrows.

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One obvious reason why warthogs live in burrows is to escape from their predators. But another important reason is for temperature control and in particular to keep warm in the cold months (1). Temperature in animals is regulated by changes in … Continue reading

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Brain Blood Flow in Owls: why they can turn their heads 270 degrees

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This blog will discuss why the owl twists his head and how it is able to do it without cutting of his brain blood supply. It was triggered by the fascinating new research by Fabian de Kok-Mercado, Michael Habib, Tim Phelps, Lydia … Continue reading

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Hyenas: the “how” of female masculinization (Part 4)

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Ambiguous genitalia at birth can be produce by genetic and/or hormonal causes. Genetic causes e.g. true hermaphrodites with gonads containing both female & male genes are very rare. More frequently ambiguous genitalia are caused by mutations in genes controlling sex hormone metabolism of … Continue reading

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Hyenas: the “how” of female masculinization (Part 3)

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In part 3 we will discuss normal mammalian testosterone metabolism using a simple input/output model. We will first look at its basic biochemistry & its influence on external genital development in the fetus. Finally in part 4, using this basic … Continue reading

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Use of art to highlight the threat of global deforestation

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I have on this blog previously questioned whether art may help in the fight against rhino poaching. I was thus intrigued to see that BBC news has just reported that Dr Iain Woodhouse, an environmental scientist at Edinburgh University in Scotland, has used art … Continue reading

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Hyenas: the why of female masculinization (Part 2)

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The disadvantages for the female hyena of having a masculinized urogenital tract when giving birth are clear (see part 1) but are there advantages for the hyena’s society of a having a masculinized and very dominant female? The “why” question … Continue reading

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Hyenas: maternal masculinization makes birth no laughing matter (part 1)

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Birth of their baby is usually fast & uncomplicated in higher primates such as gorillas, chimpanzees, & orangutans. However in man a natural birth is usually prolonged & painful. The evolution of these processes has been discussed in my previous blogs on  … Continue reading

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Cigarette butts are for the birds: toxins protect nestlings

Cigarette butts thrown from car windows along the roads or discarded all over the place in camp sites in game reserves  have always been a minor  irritation for me.  Unlike plastic bags, tins & bottles they are too small for the … Continue reading

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Can art help deter rhino poaching

We went to a wonderful art museum in the Veluwe National Park in the Netherlands. Among the van Gogh’s, Mondrian’s etc I came across the powerful work of an artist I had never previously heard of: Cai Guo-Qiang. He is, however, world-famous for his … Continue reading

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The key to understanding the neurotoxicity of snake bites: why is the mongoose immune to cobra venom (Part 3)

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In the final post on the snake venom topic we will discuss how the mongoose has been able to overcome the neurotoxic effects of cobra venom. We have learnt how ACh fits into the shape of the specific shape of … Continue reading

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The key to understanding the neurotoxicity of snake & spider bites (Part 2)

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In this blog we will discuss how different neurotoxins (snake & spider) can interfere with nerve impulse conduction & muscle contractions. We will do this using the wash basin model  to see how toxins change the effective ACh concentrations at … Continue reading

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The key to understanding the neurotoxicity of snake & spider bites (Part 1)

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I want to briefly discuss the biochemistry underlying the toxic effects of venoms trying to explain basic concepts with my beloved wash-basin analogy & also the lock & key theory. Snake & spider venom contain various toxic substances. These via … Continue reading

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Birth in Australopithecus, apes, & man: a passage over time (part 3)

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We have in the previous two parts of this 3 part series on the passage of babies through the birth canal briefly discussed the process as well as the differences  in labor between humans & the giant apes. The title … Continue reading

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Birth in Australopithecus, apes, & man: a passage over time (part 2)

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Walking into trouble: birth in higher primates. Birth of their baby is usually fast & uncomplicated in higher primates such as gorillas, chimpanzees, & orangutans. However in man the birth is usually prolonged and obstructed labor a common problem, with … Continue reading

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Birth in Australopithecus, apes, & man: a passage over time (part 1)

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I would like to discuss the differences between the birth of a baby in humans & the great apes e.g. gorillas, chimpanzees, & orangutans. In this part 1 we will first look the normal birth process. In part 2, I … Continue reading

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Not too hot and not too cold: mammals (endotherms) in the Kalahari. (Part 6)

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The Kalahari Desert can get extremely hot in summer & very cold in winter. Large & small mammals in the desert maintain their optimal temperature despite these large changes in ambient temperature. As we have previously discussed in the reptiles behavioral mechanisms … Continue reading

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Not too hot and not too cold: reptiles (ectotherms) in the Kalahari.(Part 5)

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The Kalahari desert can get extremely hot in summer & very cold in winter. Snakes & lizards in the desert have to maintain their optimal temperature despite these large changes in ambient temperature. Behavioral mechanisms play an essential role & when … Continue reading

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Not too hot and not too cold: Thermal stress & how organisms adapt? (part 4)

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Seasonal migrations in terrestrial & aquatic animals & daily choice by mammals of the right time of day for hunting illustrate how changes in temperature influence animal behavior. Temperature greatly affects all organisms & imposes limits on where they can survive … Continue reading

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Not too hot and not too cold: Jargon in heat regulation; Its Greek to me! (Part 3)

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Warm blooded and cool blooded are easily understood terms. Unfortunately in describing heat regulation of different animal species they are not always correct. There are lots of variations in how mammals, birds, reptiles, & fishes regulate their temperatures and thus … Continue reading

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Listen to the songs that dassies sing

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I didn’t realise just how interesting dassies are! Searching for their latin names for my keywords in my photography portfolio opened up a fascinating world. The information below was copied from two websites. They also have an unusual method of temperature regulation for mammals, but that … Continue reading

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Not too hot and not too cold: temperature regulation in premature babies. (Part 2)

The ins & outs of keeping a  premature  baby warm

We will discuss the difficult problem of heat regulation in the preterm human baby because the principles illustrated will help us understand heat regulation in small & large animals in hot & cold environments.

Before birth the ideal environment for growth and development of the baby is regulated by the mother. She controls the optimal input and output of energy and nutrients to the foetus, with the fine  adjustments being performed by the placenta. After birth the baby, with the continuing help of the mother, has to take over many of these processes e.g. absorption of nutrients via the intestine, excretion of waste products via the kidneys. A large energy supply is essential for rapid growth and development to continue after birth. Thus wasting of energy to keep warm must be avoided. Maintenance of an optimal energy balance is particularly important in the preterm (premature) baby. He or she is born early and has much lower glucose and fat reserves. Provision of an adequate intake of milk is not easy because the baby may have breathing problems &/or the immature intestine does not absorb milk optimally for the first weeks of postnatal life. Thus steps must be taken to prevent unnecessary energy wastage i.e. use of energy sources to keep warm instead of grow.

Heat is produced by basal metabolism as energy rich compounds e.g. glucose & fats are broken down (analogy of car engine heating up when petrol burns). This endogenous production (thermogenesis) can be increased when adults are cold by muscle metabolism: voluntary or involuntary movement (shivering). Babies, however, cannot shiver and produce extra heat by “non-shivering thermogenesis”. This heat is produced by brown fat in the back i.e. between the scapula & around the kidneys. This fat has been referred to as an “electric blanket” while normal white fat has been called a “woolen blanket” as it does not produce heat but prevents heat loss by insulation. The preterm baby has had less time in-utero to develop brown and white fat reserves & so is limited in this ability to increase heat input (shown by dotted endogenous input arrow in daigram) and decrease heat output. Thus in nursing the preterm baby exogenous heat sources are provided by using overhead radiant heaters or incubators (thick exogenous input arrow). More recently, based on research in developing countries  “Kangaroo care” has been widely adopted:  the baby is nursed on the mother’s or father’s chest in direct contact with the skin, and warmed by conductive heat exchange (see diagram).

The ins & outs of keeping a preterm baby warm (click to enlarge. Note “<”  means “decrease”)

It is also important to decrease heat loss from babies who have a relatively large surface area (see diagram showing  “<”  i.e. decreased  evaporation, convection, conduction, and radiation losses using thin dotted arrows). Unlike flexed term babies, preterm babies have poor muscle tone & lie stretched out, and this enlarged surface area increases heat loss. The baby is nursed on a rubber mattress to prevent conductive losses. The relatively large head is dressed with a padded gauze bonnet, and if the baby must be observed it is covered in plastic foil to prevent evaporative loss and/or under a transparent rigid plastic tunnel to prevent radiant heat losses. Silver foil may be used to reflect radiant heat loss when babies are transported from home to intensive care units. Modern incubators and respiratory ventilators have fine servo-control systems for regulation of humidity to prevent evaporative heat loss from the permeable skin and lung surfaces respectively. Note that immature babies cannot sweat but their initially poorly keratinized skin is very permeable and large amounts of so called “insensible skin losses” of water occur in early life.

As the preterm baby matures he is able to absorb more energy from the milk and the heat losses decrease as the skin keratin thickens and insensible water loss decreased. The baby is then placed in a cot and dressed.

We have discussed the ins and outs of heat regulation in man, and in the next blogs we will use these principles to discuss how large and small animals maintain their temperature in very hot and very cold climates.

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Not too hot & not too cold: temperature regulation in animals (part 1)

The geographical distribution of animals reflects the temperature gradients they can survive in The optimal temperature range can differ markedly in various species and the animals have developed various biochemical, physiological and behavioral  adaptations to maintain their optimal temperature as the input or output of heat varies due to activity, or climatic changes e.g. winter and summer. We will look at how the small e.g. suricates & large e.g. gemsbok animals adapt to living in the desert and how the polar bear and seals adapt to living in the arctic circle. But we will first discuss the ins and outs of heat regulation by looking at an example that all parents have experienced i.e. the human baby and in particular the problems of temperature control in the preterm baby. This will illustrate the principles which will then be discussed in relationship to wild animals.

The input output washbasin model is ideal for understanding temperature regulation as everyday examples abound. For example the temperature of a room in winter is regulated by increasing the input of heat by opening the hot water radiators or using the fireplace. The amount of heat loss is decreased by closing the windows, insulating the walls, and sealing any leaks in the door and window spaces.

Similarly we control our own temperature by altering heat input & output. The use of camping to illustrate  this, is appropriate on this blog. We increase exogenous heat input by radiation by sitting at a campfire. We can also alter the endogenous input when we are cold by increasing the own body’s production (endogenous input) by increasing our voluntary movement (clapping hands) or involuntary shivering. We can also alter our heat output. Heat loss is by four routes: radiation, conduction, convection, and evaporation. The loss from all four routes increases as the exposed surface area increases. Remember smaller “objects” have a relatively greater surface area per unit volume e.g. baby animal has a greater relative surface area than an adult animal.

The ins & outs of temperature regulation (click to enlarge)

So when camping we try to decrease heat loss by these routes. We decrease our surface area by flexing our limbs.Radiant loss is decreased by sleeping on a mattress with a silver foil lining. Conductive loss is decreased by an air cell/rubber mattress and thick clothes. Convective losses from the wind are decreased by sleeping indoors or wearing windproof clothing i.e.”windstopper”. Evaporative heat loss is decreased by getting out of wet clothes as soon as possible. It is now easy to work out the steps we take to cool down e.g. stretch out to increase surface area, sit in shade & decrease activity, less clothes, swim, use a fan.

In the next blog we will discuss the ins & outs of heat balance in preterm babies

 

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Understanding exposure in digital photography (Part 2)

As discussed in part 1 of the blog on exposure in digital photography I feel the widely used “bucket” analogy does not explain the ISO setting clearly. We will here via three figures gradually expand the object bucket to use “watering the lawn” to explain exposure. watering the lawn entails providing enough water by increasing the duration or increasing the diameter of the water spray head. This is similar to the variables in filling a bucket. But the amount of water on the lawn that will actually penetrate to the roots of the grass will depend on the porosity of the soil i.e. spiking the lawn will  increase penetration. So the soil is then  more “sensitive”to the water analogous to the sensor becoming more sensitive to light as the ISO increases. So now we have an analogy with the three settings needed to understand the “exposure triangle” of aperture, shutter speed, and ISO values.bucket model

 

alwn model for camera exposure

Watering the lawn (Figure 2b)

expanding lawn model for camera exposure

Exposure settings explained using “lawn” analogy (Figure 2c)

 Finally a brief discussion on how ISO is physically altered in your camera. With the camera sensor sensitivity is modified by amplification of the available  light signal to a greater electrical signal. This amplification is similar to that in a HIFI system: the audio amplifier will increase the sound level. But amplification of sound or light will potentially also increase the “noise”. This is termed the signal/noise ratio. With sound you hear an increased hissing noise relative to the music. With  light,  increasing the amplification i.e. higher ISO more noise is produced i.e.  a scattering of light (“speckling”) called luminance noise or blocks of colour called chrominance noise.

Please refer to the excellent website “Cambridge in colour” for further detailed explanations of all aspects of photography

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Understanding exposure in digital photography (part 1)

To write with light i.e. photography, sufficient light energy (photons) must reach the sensor. As the light can vary e.g. outdoors or indoors, cloudy or sunny day, sunrise & sunset, or midday one, must be able to adjust the camera settings to capture enough light in different r i.e. obtain the correct exposure. This is done by altering one or more of the following three settings: aperture size, shutter speed, and the ISO value (sensor sensitivity). The interaction of these settings is often explained using the bucket model.

Bucket model does not adequately explain the role of ISO settings in exposure (click on image to enlarge)

The site referred to is fantastic and I have learnt a great deal on all aspects of photography there, but I feel the bucket model is inadequate to explain exposure clearly. It explains two variables aperture diameter and shutter speed simply and clearly but the role of the ISO is not clear in the bucket model.

We modestly suggest that a better model is “watering the garden lawn” as that allows the porosity of the ground  to be used as an analogy for sensor sensitivity. This makes changes in the ISO value easier to understand. At least I hope so. This will be discussed in the next blogs.

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Introduction to using the Milkshake flow model

As explained earlier I try to simplify difficult concepts by using everyday analogies. These simple objects e.g. milkshakes are repeatedly used. This does obviously sometimes result in “poetic scientific licence”. For example the milk shake, will not only be used to simplify Poiseuille’s Law to describe blood flow, but also be used in adapted forms  to explain subjects for which it was not intended e.g. discussion of light flowing into camera, or how the open fontanelle and skull sutures allow the birth of a baby to “flow” more easily. I believe the repeated use of this flow analogy, though taking many liberties, makes it easy for the non expert to understand diverse subjects (Q.E.D.).

In this blog Poiseuille’s law is dramatically simplified (see drawing) to explain how to drink a milkshake quickly.

Very simplified Poiseuille’s Law (click drawing to enlarge)

 

The concepts discussed here will be next used to discuss factors as diverse as adjusting exposure in your digital camera and the role of open skull sutures in the birth of Australopithecus africanus babies a million years ago!

Please be patient, and at least give me a chance to try & explain these subjects in object oriented analogies in future blogs.

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The visual cycle (part 2)

The Rhodopsin cycle (click on drawing to enlarge)

The ability to see in the dark depends on an adequate concentration of retinal. The ins and outs of photosenstive cis retinal and its recycling  from trans-retinal are illustrated here.

Photo-receptors e.g. the eye, have the ability to convert light’s energy in photons to electrical impulses. These signals are then carried in nerve cells to the brain to be interpreted e.g. shape or color. Although the physical structure of the “eye” is very different in different animal species, the chemical reaction that captures lights energy is highly conserved. Thus studies in the Drosophila fruit fly have answered many questions about the visual cycle of the vertebrate eye! The photosensitive visual molecule Rhodopsin consists of a protein called opsin, coupled with retinal, which is the light sensitive component. As discussed in part 1 of the visual cycle on this blog, Vitamin A (retinol) is an essential vitamin i.e. supplied in the diet, and is the precursor of retinal.

Rhodopsin comes in different variants, which respond to different quantities and qualities of light. The molecule is held in the plasma membranes of two types of cells in the retina: the rods and the cones. These names describe the shape of the cells as seen under the microscope. The rods, mainly found in the periphery of the retina respond to small amounts of light i.e. work well when the iris dilates in dim light. The cones are found centrally, and respond best to bright light. They enable us to discern colours and detail. The opsin protein has several helices traversing the plasma membranes and these form a pocket to hold the retinal . The latter, in its “cis-retinal” form is the photosensitive part of the molecule. In the dark it holds the opsin in an inactive shape. But when activated by light it converts to “trans-retinal” and this pushes the opsin into an active form. This triggers a cascade of events altering the permeability of the cell membrane and a signal of light and/or color is conducted to the brain by the optic nerves for interpretation. The photo-activated trans-retinal cannot be reused until it is converted back into an active cis-retinal form. This is known as the visual or rhodopsin cycle. It is transported from the rod or cone cell cytoplasm, and released into the sub-retinal space, where it is bound to a transporting protein and carried into the retinal pigment cell for reconversion again to active cis-retinal. The recycling and production of new supplies of retinal from beta carotene and retinol occur in the retinal pigment layer. This explains why the rods and cones lie between the nerve cells and this pigment layer. This allows more efficient recycling of cis- retinal. Nevertheless regeneration and transport of cis-retinal takes time, and explains why we are temporarily blinded when a bright flash of light depletes all the retinal bound to opsins in the rods. As discussed in “trip tips” this is the reason why flashlight photography and spot-lights may disturb nocturnal animals and birds. The duration of the resulting night blindness depends on the speed of retinal recycling, but takes up to 30 minutes for complete recovery. It is interesting to note that cone cells, used in bright light, have supplementary cis-retinal recycling from helper  Mϋeller neural glial cells in the retina

The pupil appears dark because of the black retinal pigment layer which absorbs almost all the light. Apparently only 0.1% of the light entering the human eyed gets reflected out again i.e. pupil is black. Although the opsins are not photosensitive, variation in their composition accounts for our ability to respond to and see different colors. There are 3 types of cone cells each responsive to a particular wave length of light i.e. the three primary colors red, green, and blue.

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Vitamin A Metabolism:

Vitamin A Metabolism (click on drawing to enlarge)

An adequate concentration of vitamin A in its storage depot, the liver depends on the balance between the input and the output. In this example, using the  “wash basin model” to analyse a biological process, note that the concentration of the metabolite (vitamin A) is influenced more by its input than its output. Future examples in the blog e.g. hydration, acid/base balance, will show that both input and output can be major determinants

Vitamins cannot be synthesized in animals and are supplied in the diet i.e. exogenous input. Vitamin A is one of the fat soluble vitamin group i.e. vitamins A, D, E, and K, and so an adequate supply depends on efficient fat absorption in the intestine. Vitamin A is a term referring to a group of compounds: retinol, retinal, and carotenoids including β carotene, which is a precursor of retinol. Vitamin A is stored in fat depots e.g. liver and a vitamin A deficient diet must continue for a long time before a deficiency will occur. Deficiency of vitamin A is rare in the developed world because of adequate diets and vitamin supplementation. It occurs when there is an inadequate input due to a poor diet e.g. malnutrition or malabsorption of fat. Fat absorption requires synergistic action of bile from the liver and lipase enzyme from the pancreas. Bile acts as a soap emulsifying the lipids into small fat globules which have a larger surface area (analogous to small animals losing more heat because of their relatively larger surface area) allowing easier attachment and digestion by lipase. The released fatty acids are absorbed by intestinal cells, and then pass via the lymphatic system of the intestine into the blood stream for transport to the liver. Thus vitamin A deficiency occurs in patients with liver, pancreatic, or intestinal diseases. However an excess input of vitamin A e.g. an overdose of multivitamins can produce serious side effects e.g. brain swelling. Excess β carotene ingestion occurs in people on fad diets. I remember many years ago an acquaintance turned yellow. He thought he had liver disease, but it was “carotinemia” due to his passion for pumpkin!  Interestingly enough, although it is a precursor of retinol, the side effect of “carotinemia” is limited to the transient yellow discoloration of the skin. The output of vitamin A is mainly via its metabolism in various organs. But it is also excreted exogenously via the kidneys, and excess levels can occur in renal failure.

The vitamin A is stored as retinol in the liver and then transported to tissues e.g. the retina as required. Retinol is not water-soluble, and it is transported in blood plasma bound to a protein, the “retinol binding protein” (RBP). Tissue cells can take up the retinol via a cellular retinol binding protein. The retinol plays an essential role in cell differentiation, gene expression, and fetal development. But our particular interest in this vitamin is because of its role in the visual cycle and night vision. It is interesting to note that the ancient Egyptians knew that feeding liver would cure night blindness.

It is clear that vitamin A metabolism is very complex. Details are given in these two references (a) and (b) . But for our purposes  just remember that the concentration in our cells depends on a balance between its input and output. Its significance for our discussion is that it is an essential component in night vision. The visual cycle, which will be discussed in the next post, will now be easier to understand (hopefully!).

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Simple explanations of difficult biological concepts.

I retired seven years ago, but still believe that teaching could be made easier by repeated use of  simple models. For example in medicine each speciality e.g. pediatrics, geriatrics has its own approach. This is effective for the specialist, but difficult for the student who must migrate from one speciality to the other during his training, each time learning a different method. It would be a lot easier for them if the approach to the diagnosis and treatment of disease emphasized the similarities in these processes in all age groups and specialities (See for example: The ins and outs of respiratory distress syndrome in babies and adults. J R Coll Physicians Lond. 1994;28:24-33). I could not convince my peers to introduce this “object-oriented” approach. Oh well, that’s in the past. But now as I try to develop my blog on biology I find myself again reverting to the object-oriented approach when trying to explain biological processes. Thus today I want to introduce you to the “object-oriented” approach to teaching and learning.  It first explains simple and well-known processes e.g. filling or emptying a wash basin (input & output), or speed of flow through a straw  when drinking a milkshake (suction pressure, diameter of straw, viscosity). Then it expands these “objects” to explain factors influencing complex biological events e.g. temperature control  or blood flow.

I first encountered the wash basin scheme when two eminent scientists in the 60’s & 70’s used it to explain calcium and acid base balance. They did this by explaining the factors that would influence their input or output.  I realized that this model could be useful for understanding many other day-to-day medical problems. I adopted and adapted their ideas, and later added in the “milkshake model” to help simply analyze other problems related to flow e.g. circulation and ventilation. These two object-oriented models with variations dominated my approach to clinical work, research, and teaching for the rest of my career. Looks like wash basins and milk shakes may attempt a comeback on this blog!!

 click on image to enlarge

I will return to these  models repeatedly in the months to come e.g. temperature and fluid balance in desert animals.  However, I have in “trip tips” on the website just discussed the effect of spotlights on nocturnal animals. Thus I will first try to explain how adequate concentrations of vitamin A and retinol, essential for night vision, are maintained.

It is interesting to note that the painter Cezanne believed that complex images could be broken down to simple geometric forms (objects). He wrote “Treat nature by means of the cylinder, the sphere, the cone”. This philosophy can be recognized in his wonderful paintings.

 

Objects are also the key to understanding “object-oriented” programming languages. Thus the characteristics of an object are encapsulated within it e.g. a wash basin be coded as having e.g. an input and an output, and these characteristics will inherited  by all its “offspring” objects e.g. controlling the temperature of a room. Similarly if flow of water is programmed as an object all subsequent flow “offspring” e.g. blood flow, will inherit these characteristics.

So reduction of difficult concepts into simpler forms has been used in many fields. I believe it should be more commonly used in biology to make scientific concepts easier to understand for the general reader. Long live object oriented thinking!

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The slow evolution from blabbing to blogging

I have spent the last weeks editing our 2011 photographs  and updating the tip pages. Some of the tips are taking a lot of time. For example giving advice on malaria. There are expert sites for this subject, and giving unsound advice would be a terrible mistake. Therefore I spent a great deal of time searching for sites with up to date and clearly explained information. There the traveller can get detailed information about current measures to prevent malaria long before starting their trip to Africa. The aim of our site is to summarise and collate the information, and illustrate it with the products we have chosen to use e.g. permethrin treated clothes, time release DEET lotion. We hope our summary will decrease the time other safari goers will need to understand this important subject, and help clarify their questions before their  essential consultations with their general practitioner and travel clinic.  The South African Parks Board forum has excellent information forums. It has an ongoing discussion on malaria prevention. But this particular topic  has not been updated since 2008. It has an overload of anecdotal advice from well-meaning contributors. Wading through 81 pages to get essential advice is not what a traveller needs. Hopefully experts will update the advice in the near future. I will then add it to the list of presently recommended sites on my travel tips page.

But in these two weeks I have also spent a lot of time thinking about the purpose of my blog. I do not indulge in Facebook or Twitter and I must admit the idea of having a page to express my weird ideas is appealing. However I would like it to be than just self therapy for an old age adventurer!

The ideas for this blog are still evolving, but probably the best would be for me to use  knowledge of human biology and adaptation  to interpret interesting but sometimes difficult general biological questions. I will search for current and old topics on biology  and see if I am able to explain them clearly for the general reader. At the moment I am writing a photography tip about the effects of photographic flash on animals eyes. This has lead me down a new path. The evolution of light receptors in invertebrates and vertebrates, and the conservation of rhodopsin as the visual pigment in all these species is  a fascinating story. This is too much for the photography tips page, and I hope some readers will find it interesting reading if I briefly elaborate on it  on this blog. It will take time for me to understand it and explain it simply. So hold on a few days!

But a tit-bit for now. I was amazed today to find my adventure on the genetics of visual pigments leading me to a music site. Two scientists have composed music based on genetic and amino acid patterns! Listen to it on internet! Enjoy!

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Getting blogging site up takes patience and lots of friendly help

The decision to start a photographic site has had many intellectual repercussions. Through my work,  I had previously developed an  interest in the role of computers in teaching medicine. But this really only amounted to the use of art and simple input output models in Powerpoint presentations. Very basic Flash animations were also used to illustrate the physiology and pathology of  newborn babies. I however, had never learnt the principles of coding or programming in any form.

Starting the photographic website was the beginning of a new exciting journey. An American photographer recommended that we use SMUGMUG to build our photographic site builder during a casual chat at a waterhole. I am so glad we took his advice. This company provides absolutely superb service and help for beginners like me.

You can start with easy customization and then as your courage grows, very slowly add in your own coding with HTML, CSS, and JS. In my case, that still mainly amounts to asking their great team what to do. They will rapidly give advice and provide the required code to  paste into the  HTML, CSS, or JS blocks. However with help of books one gradually rises (or sinks) into this rarefied atmosphere, and one begins to believe (??) “I can do that”. Enthusiasm and optimism have unfortunately always been my only talents!

I have now also started a blog and the little triumphs e.g. changing the photograph of the header page today to the lion landscape are the kicks that do keep an old man a bit younger.

But there is something more fundamental:-

a)The BBC news and many newspapers have been full of the theme “Coding is the new latin”, with the mayors of New York & London also threatening to start learning the basic coding languages. Thus I also joined the free Code Academy which gently and gradually teaches coding e.g. Javascript and HTML, with more courses being developed.

At the moment I forget the lessons quicker than I can use them, but I am beginning to understand the help pages on internet or in dummies’ guides on building websites and blogs. Hold thumbs, I just may live long enough to get to grips with all these languages. But more important is the increasing evidence that if you don’t use it you lose it”, referring in my case to cerebral activity. We like to think of ourselves as old age adventurers. But the adventures are of course not only waiting in Africa but also present at home e.g. on internet. But in general trying another hobby and learning a new skill, as you age, appears to open new circuits in the brain, which surprisingly retains its plasticity even as it ages.

b) You can bore the pants of your children and tennis mates.

c) And most important of all you can teach the grandchildren, even the very young ones to create and share interactive games and music etc. But for that use “SCRATCH” developed by MIT to teach children object-oriented programming, and available in many languages. Try it as it even works when you are above 70 years of age. Have a  peep at http://scratch.mit.edu and you will be phoning the grandchildren to offer to baby sit. You will be able in a short time to program using “Lego like computer “” blocks. Although to be honest in our family this project has suffered due to our long trips in Africa. But time for a new kick-start this summer.

 

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