Kidney development
As we develop in the womb, we form three sets of kidneys. The pronephroi ('forekidneys') are non-functional and appear in the fourth week; they soon degenerate, but the ducts are recycled in the... mesonephroi ('midkidneys'). These contain glomeruli and tubules; they degenerate during the first trimester, but the tubules are recycled in the... metanephroi ('hindkidneys'), which are our permanent kidneys. As my copy of Moore & Persaud's The Developing Human says, the pronephroi correspond to the kidneys of primitive fishes, and the mesonephroi to the kidneys of fish and amphibians.It has been suggested that these things are necessary as scaffolding for the final kidneys, since some bits are reused. However this is rather like building an Eiffel Tower as scaffolding for another Eiffel Tower, which is used as scaffolding for a final bigger Eiffel Tower, ripping down each one along the way. (Intelligent Design proponents normally seem to avoid scaffolding arguments.)
Useless eyes: cave critters
| There are hundreds of species of animal which, living in total darkness in deep caves, have no need for eyes. They range from fish (eg the Mexican blind cave tetra Astyanax fasciatus mexicanus) to insects (eg the Hawaiian cave planthopper Oliarus polyphemus), spiders (eg the Tooth Cave Spider Neoleptoneta myopica), salamanders (egTyphlomolge rathbuni) and crayfish (eg the Dougherty Plain cave crayfish Cambarus cryptodytes). Yet, these creatures do in fact have eyes. The eyes are often tiny, lacking crucial parts, and so on, and so they would not function even if there were light to see. But they are clearly eyes, set in skull apertures, on stalks etc as normal, nevertheless. Eyes that don't work in creatures that don't even need eyes? Surely not?! |
Useless eyes: burrowers
Many burrowing animals have non-functioning eyes, such as marsupial moles (order Notoryctemorphia: no lens or pupil, reduced optic nerve), golden moles, amphisbaeneans and naked mole rats (Heterocephalus glaber).
Useless eyes: river dolphins
Not all river dolphins are blind; in fact, Amazon dolphins (Inia geoffrensis) have quite good eyesight. However, most others have reduced vision. Most of their habitats are murky waters, where eyes are of little use. And the designer's gift of good sonar is perfectly adequate instead. Why, then, do Ganges and Indus dolphins (Platanista gangetica and P minor) have eyes at all? For their eyes lack a lens, leaving these species unable to resolve images: the most they can do is perceive the presence or absence of light (of which there's rather little where they live anyway)... for which skull apertures, eyeballs, muscles, retinas and the rest, the same design as normally-sighted dolphins have, seems a bit excessive.
Nautilus eyes
Whilst on eyes... is it not strange that the creator, having given the nautilus (Nautilus pompilius) an otherwise very good pinhole camera eye, chose not to give that eye a lens?
Tarsier eyes
| Tarsier skull Picture courtesy Bone Clones® | Most nocturnal vertebrates, from owls to cats, have a membrane behind their (backward) retina, the tapetum lucidum. This reflects back any stray photons, giving the retinal pigments a second chance to pick them up. Seems like a good idea, yes?It is strange, therefore, that the creator saw fit to omit this apparently very useful piece of design from nocturnal tarsiers (and other nocturnal primates, such as bushbabies, owl monkeys etc). These cute little prosimians clearly need to see well at night. At least, we can assume so, because they have eyes so huge that each is larger than their entire brain! These vast eyes can barely be swivelled in their sockets, so the tarsier design requires the addition of an extremely rotatable neck. If they were designed to see in the dark, think how much better they could do so with a tapetum lucidum behind each retina too! Alternatively, if they had one, perhaps they would not need such huge eyes. A waste of materials, perhaps? Or might this be design constrained by history? (The designer also forgot to include a tapetum lucidum in the eyes of owlet nightjars (Aegothelidae) and the Galapagos swallow-tailed gull, both of which, being nocturnal, would presumably benefit from having it. And he obviously was not bothered about the low-light visual abilities of humans either, for we too lack a tapetum.) |
Mammalian vision processing
Also strange is the fact that the part of the mammalian brain that does the image processing is at the back of the head, so the nerve signals have to travel further from the eyes than they might otherwise need to.
The vertebrate retina
The retina is the 'screen' at the inside back of each eyeball, onto which is projected the incoming light. It is made up of lots of photoreceptor cells with their associated out-going nerves, and the blood supply to them. The problem is, the photoreceptors are in backwards, pointing away from the incoming light: the 'cable' from each cell is therefore in the way, and trails across the eyeball's inside surface to exit the retina at the correctly-named 'blind spot'.
Now, the brain compensates for this, so we don't usually notice it. But a design that needs compensatory mechanism for some aspect of it, is not a good design.
But to make matters worse, this design actually causes unnecessary problems.
The photoreceptors have delicate, hair-like nerve endings, which means they cannot be cemented firmly into place. Instead, they are loosely joined to a layer of cells called the retinal pigment epithelium. This absorbs stray photons that would otherwise blur the image, and contains the retina's blood supply. But the connection between the retina and the epithelium is so fragile that the retina can detach, either due to a blow to the head, or often, spontaneously. Starved of their blood supply, the retinal cells die, causing blindness.
Strangely, the creator was able to put retinas the 'right' way round... in those pinnacles of His purpose, the octopus and squid. Not only do their eyes, which are basically the same design as vertebrate ones, have their photoreceptors pointing towards the light, and so lack a blind spot; with the nerves training behind them and embedded in their blood supply, the cephalopod eye is far less prone to detached retinas.
Locust wing nerve 'wiring'
In the African locust (Locusta migratoria), the nerve cells that connect to the wings originate in the abdomen, even though the wings are on the thorax. Nerve signals from the brain have to travel down the ventral nerve cord past their target, then backtrack through the insect to where they are needed.
The recurrent laryngeal nerve
The nerve 'wiring' of the mammalian larynx is also bizarre. Nerve signals for bodily operations travel from the brain down the spine, then branch off. Fair enough. The larynx is in the neck, so one might expect that the relevant nerve would come off the spine at the neck. And, it does: the recurrent laryngeal nerve originates from the spinal cord in the neck, as a branch of the vagus nerve. But then, bizarrely, rather than taking a direct route across the neck, it instead passes down the neck and into the chest, loops under the posterior side of the aorta by the heart, then travels right back up again to the larynx. Which is a waste of materials by anyone's standard, but in the case of the giraffe, it implies a Creator so set on the mammalian Bauplan that an extra 10 to 15 feet of nerve is needed.
More on the recurrent laryngeal nerve here.
The human larynx-pharynx junction
Talking of larynxes, there's the opening of the human larynx (leading to the trachea) being from the pharynx, so that swallowing impedes breathing (and vice versa). Not only that, but with the wind-pipe coming from off the food-pipe, there is a constant risk of choking. Before the Heimlich manoeuvre was invented, choking was one of the leading causes of accidental death; even so, thousands still die worldwide each year from inhaling their food. Children are more vulnerable because their airways are narrower. Great design.
Human ear-moving muscles
The cartilage-y bits which funnel sounds into the sides of our heads, which we usually call 'ears', are known more formally as pinnae or auriculae. (It's actually only the most external part of the external ear, which is everything up to the tympanum (eardrum). And the human pinna (or auricula) has three muscles attached to it: the Auriculares anterior, superior, and posteriore. They naturally have a blood supply, and their own nerve wiring (by a facial nerve -- the temporal and posterior auricular branches of cranial nerve VII).
Yet, as Gray's Anatomy puts it, "In man, these muscles possess very little action: the Auricularis anterior draws the auricula forward and upward; the Auricularis superior slightly raises it; and the Auricularis posterior draws it backward". They move our ears.
In other mammals however, these muscles possess a very useful action, rotating the funnel that is the pinna to point towards sounds. Human ears, being more or less flat and fixed to the sides of our heads, cannot rotate towards sounds... which doesn't stop these muscles giving it a feeble go.
The ability of some people to wiggle their ears is, sadly, one of the Unidentifiable Flying Intelligent Designer's lesser-appreciated gifts to us.
Aquatic embryos
Terrestrial salamanders, which live their whole lives on the land after hatching, have to return to water to lay their eggs.
Sea turtle eggs
Conversely, aquatic creatures such as sea turtles, which spend their whole lives at sea, have to struggle out onto land in order to lay their eggs.
Gill-less cetaceans
Cetaceans -- dolphins and whales -- have to breathe air, and despite being designed to live underwater, have to return to the surface regularly to catch their breath. They do not drown, since they do not inhale underwater, but they can suffocate if they don't get to the surface in time.
This is especially a problem for newborn calves, which are born underwater. Taking the first breath is triggered by the touch of air on the skin, and post mortems of dead calves sometimes show that it never got to the surface to take that first breath.
So, why no gills? It's not like the designer couldn't include both gills and lungs if it saw fit, since salamanders and lungfish have both -- though it is unclear why cetaceans should have to breathe air at all.
What's more, cetaceans can suffer from the 'bends' -- decompression sickness -- if they surface too quickly, just like any other mammal. This is where nitrogen in the lungs -- lungs, yeah? -- is squeezed by the depth pressure out into the bloodstream as bubbles. When the mammal surfaces from depth, a lot of time needs to be taken so that the bubbles can be safely, gradually, returned to the lungs. So, whales don't usually surface very quickly. But if they do, they can die just as unpleasantly as any other mammal in that condition. And odd thing for a creature designed by a high intelligence to be able to suffer from, no?
See:
- How do whales and dolphins sleep without drowning?
- Jepson et al, 'Gas-bubble lesions in stranded cetaceans', Nature 425, 575-576 (9 October 2003)
- BBC: Noise pollution hurting whales and dolphins
Haemoglobin
Haemoglobin, the molecule which transports oxygen around our bodies in red blood cells, has more affinity for carbon monoxide than for oxygen. It is better at carrying this poisonous gas than at the job it was so intricately designed to do.
Mammalian foetal blood circulation
There's two problems here. Firstly, in the mammalian foetus, the lungs are not yet functional, and the oxygen and carbon dioxide exchange takes place in the placenta. Here, oxygenated blood coming into the foetus mixes with deoxygenated blood that has already circulated. This is very inefficient, as it means much of the foetal body receives only partially oxygenated blood. In adults, the deoxygenated blood goes directly to the lungs for oxygenation before circulation to the rest of the body; the mixing does not happen because of the closed connection between the heart and the lungs.
Secondly, to make this rather circuitous circulation possible, there is a hole between the chambers in the foetal heart (the foramen ovale), and foetal blood vessels (eg the ductus arteriosus). These need to close off at birth for the transition to adult circulation. Sometimes they don't, leading to two relatively common, and sometimes fatal, birth defects -- so-called 'hole-in-the-heart' babies.
Could the designer have done it better? Sure! If the umbilical cord were inserted at the chest, rather than the belly, it would solve several of these problems, because the umbilical vein and umbilical artery could connect to the pulmonary vein and pulmonary artery. If this doesn't take a genius to work out, where does that leave the designer?
Many thanks to Mr Darwin at IIDB for this item.
Snake lungs
The lungs of snakes such as blindsnakes and colubroids. They have two lungs in their elongated bodies: a 'normal' sized right lung, and a tiny left one. Why waste material with the small one? More surface area for respiration would be available if the space the little lung's non-gaseous-exchange tubing takes up were given over, instead, to a larger-volumed single lung. After all, that is what is found in other snakes.
Amphisbaenean lungs
Amphisbaeneans -- 'worm-lizards' -- have the same oddity as the colubroid snakes above... but in them, it is the right lung that is reduced. The designer clearly couldn't decide which poor design to stick with!
Cephalopod gills
The flow of blood and water through the gills of cephalopod molluscs (octopus and squid) is not a counterflow arrangement, and so the gills are far less efficient than they could be. Sure, they're good, but they're good despite this disadvantage. Counterflow systems, where two fluids move in opposite directions, maintaining as high a concentration gradient as possible the whole time, are so useful that they are found in a wide range of situations: lungs, fish gills, kidneys, cold-adapted animals' circulation (eg penguin feet), and so on. Yet the designer decided against using this basic arrangement... only in cephalopods...?
Snake pelvises
Many species of more 'primitive' snakes (that is, creatues without legs, yeah?), such as pythons, have bits of pelvis, hindlimbs and hindlimb claws buried inside their bodies. These are, of course, of immense use to legless creatures.
Whale pelvises
Whales have, buried deep in their bodies, remnants of pelvis and hind limb bones. Even if (as is sometimes claimed) they do have a function, why are the bones in question bits of pelvis and limb?
Manatee pelvises
Similarly, manatees have small, free-floating, paired pelvic bones located in the body-wall musculature. Why?
See Fagone et al (2000): 'Sexual dimorphism in vestigial pelvic bones of Florida manatees'. Florida Scientist 63(3): 177-181; Shapiro et al (2006): 'Parallel Genetic Origins of Pelvic Reduction in Vertebrates'. PNAS Vol. 103, No. 37, pp. 13753-13758.
The panda's thumb
A main part of a giant panda's diet is bamboo, which it grips with its forepaws. Gripping roughly-cylindrical objects is best done if you spread your gripping equipment around the shaft of the cylinder, so you can squeeze it. To do this, pandas have, like us, a thumb. However, the panda's 'thumb' isn't a true thumb, a digit, at all. They have a relatively normal bear-like five-digit paw... and the 'thumb is an altered wristbone, the radial sesamoid.
If the human hand were the ideal design, we should expect a normal thumb, not some different way of doing the same thing. And if six 'fingers' are better than five for grasping, why do only pandas have this feature?
Chameleon feet
| Photo: Art Wolfe [Masters of Disguise: A Natural History of Chameleons by James Martin] | Chameleons spend their time clambering around in trees -- that is, holding onto cylindrical-ish objects (branches). And so, like pandas and primates, they need a divided gripping tool... and they have one (well, four). But the chameleon's design is different again. Rather than a thumb and four (or five) fingers, they have, in effect, two thumbs and three fingers. The designer clearly couldn't make up his mind as to which design was best. But it is reasonable to assume that two thumbs are stronger than one, and that the two-three arrangement makes the grip more even (and so, more effective: pliers, for instance, don't have a strong wide jaw and a thin, weaker one). Which would make the primate one-four grip a less efficient design. One might also wonder why the designer kept using five digits. For what design purpose does the chameleon have two-three, rather than, say, three-three (or two-two, or any other combination)? |
Male mammal nipples
Male mammals have nipples. They do so because, in the embryo, the tissues involved start to develop before the two sorts of bodies (male and female) diverge. But given that most other sex differences are confined, naturally, to the separate sexes, it is a remarkably odd bit of design. Males, after all, do not and cannot feed their infants with these nipples. Why are they then not pointless and a waste of materials?
Almost as interesting is the fact that male nipples are fully capable of feeding an infant. If a man is given the right hormones, and he will grow breasts that will lactate. So males potentially could feed infants. Surely that would be an obviously beneficial trick? But no. The Lord giveth, and the Lord taketh away, it seems.
Waste of life
There is a phenomenal waste of life in nature, everywhere you look:
- Oak trees produce thousands of acorns, yet hardly any stand a chance of becoming trees.
- Many fish species produce thousands of eggs, in the hope that a few will survive. Herring (Clupea harengus) for example produce around 35,000 eggs per batch, while cod (Gadus morhua) produce about four million.
- Male animals produce millions and millions of sperm, yet almost none stand a chance of fertilising an egg. A human male produces around 350 million sperm at each 'shot'. The garden snail Helix aspersa, for instance, is hermaphroditic; sex is generally repeated with around six partners during a mating season. Sperm from each partner have to fight their way up the reproductive system past a cavity called the bursa copulatrix. Only the fittest will arrive at their destination, a special vessel where they may be stored for as long as four years while they are gradually used to fertilise the snail's eggs. As many as 99.98% of them will die and be digested before they reach their goal, the storage organ.
- Hundreds of millions of tons of pollen are cast into the air every year, with only the tiniest of fractions reaching its desired destination. (Mind you, compare Genesis 38:9-10: wasting one's gametes was a serious enough sin for Onan to be killed in punishment. Yet the Good Lord is supposed to have created things which by their very nature spill so much seed on the ground?).
- Approximately a third of human pregnancies fail or spontaneously miscarry in the first trimester.
- Male elephant seals battle so furiously for females that great numbers of them die of bloody wounds.
- When a male lion takes over a pride, it will usually kill the cubs of the previous top male.
- The boom and (catastrophic for the individuals) bust of lemming populations.
Functionless flowers
Flowers on plants such as dandelions, which are apomictic (asexual) and thus do not need to attract pollinating insects. Many apomictic species also continue to produce pollen, which may trigger reproduction, but its genetic contribution is not used and is thus wasted.
Functionless flower parts
The non-functional stamens (male parts) in some female flowers, and the non-functional pistils (female parts) in some male flowers. Most flowers have both sexes of reproductive organs (stamens and pistils). Some however have only one or the other, making the flower male or female. So having both where only one set works is a waste of materials.
Poinsettia bracts
Poinsettia flowers have tiny petals. Fair enough, one might think. But they are insect-pollinated, and so attract insects... not with their petals, but by having the top leaves round the flowerhead turn bright red. So what we have here, on your windowsill or table at Christmas, is an insect- pollinated plant with red leaves that could have been used for photosynthesis, and useless little petals. (Evolution has a simple answer to this re-invention of the petal: poinsettias belong to a family of angiosperms (flowering plants) called Spurges, which in general have lost their petals and altered their methods of pollination. Poinsettias have re-evolved insect attraction in order to be pollinated, but rather than regrowing petals, the top leaves do the job.)
Snail sex
Sex for molluscs such as the garden snail mentioned above is no easy affair. After finding a mate, courting may take up to six hours, and involves circling, tentacle touching, and lip and genital biting. Finally they get together and, being hermaphrodites, insert their penises into one another. As they live in shells, their genitals are located in their heads. They then fire 1cm long calcium carbonate darts into each other.
Back when I was at school, I was told that these served to hold them together, but the truth is much stranger. The darts' job is not to fix the snails together, but to fix the sperm contest in favour of the dart-thrower, by ensuring more of its sperm make it to the storage chamber.
The darts are fired as sex begins. As they plunge into the partner's body like hypodermic needles, they transfer a chemical called allohormone. This makes the female part of the reproductive system contract, sealing off the entrance to the bursa copulatrix, and diverting the sperm straight to the storage organ. A snail that has been speared will store twice as much of its partner's sperm as a snail that has not.
A design elegant in its simplicity? Nah...
(As reported in New Scientist, 2 November 2002.)
Spider penises
They don't have them. Now, internal fertilisation of egg by sperm seems to be a Good Idea: it is an effective way to ensure that the gametes meet. This can be accomplished by the female squatting over a sperm packet; that is how some mites do it. But more obviously and, one might think, sensibly, males often have a penis -- a structure to deliver the sperm.
A male spider delivers his sperm with his pedipalps. These appendages are located on his head (and are considered by evolutionists to be modified mouthparts). But inconveniently for the spider, the pedipalps are not connected to the part of the body where the sperm is made (spider gonads are, unsurprisingly, located in the abdomen).
So before copulating, the male deposits his sperm onto a small web he has spun especially for this purpose. He then siphons the sperm up into the pedipalps, like "drawing ink into a fountain pen" as Olivia Judson has described it. Only once his pedipalps are thus primed can he inseminate his mate.
Surely having the gonads connected to the pedipalps... or a penis-type arrangement located, well, anywhere the designer felt like, really... would be a simpler and more economical design...?
See eg: W S Bristowe (1958), The World of Spiders, p65-67.
Spider penises 2: too heavy, too many
Having filled up their pedipalps, male spiders then set off in search of a willing female. The problem is, thus loaded, the pedipalps are relatively heavy to lug around.
Now, if it also so happens that your mate is much larger than yourself, you can't have a copulatory organ that is, well, too small to satisfy her, and thus you can't get away with simply having a smaller organ to lighten your load. So firstly, one wonders why the designer, having decided that the male of some some spider species should be much much smaller than their mates, didn't make her parts more suitable in dimension for him. But that's not the half of it.
In one spider species, Tidarren, the males are tiny, weighing only about 1% of their females. Yet Tidarren males would still have to try to run around with relatively huge (20% of their body weight), loaded pedipalps. And it would slow them down... which would mean they couldn't cover as much ground in search of a mate.
Why 'would'? Because, before he reaches maturity, a Tidarren male spins a bit of web, sticks one of its pedipalps into it, and then twists it off.
And yes, they can, therefore, run faster (44%), further (300%) and for longer (63%) with their genitals in this singular condition.
One has to wonder why, if one pedipalp is sufficient, the designer gave Tidarren males two. Talk about well endowed!
See Ramos et al (2004): 'Overcoming an evolutionary conflict: Removal of a reproductive organ greatly increases locomotor performance'. PNAS Vol. 101, No. 14, pp. 4883-4887.
Spotted hyaena reproduction
There are certain... oddities... about the reproductive system of the spotted hyaena (Crocuta crocuta). But I can do no better here than quote from this site (my emphases):
| Female spotted hyenas bear, suckle, and care for their young like any female mammal. But although their genitals are clearly female in function, they are male in form. The labia are fused into what looks like a scrotum, complete with two pads of fatty tissue that resemble testes. In addition, the clitoris is elongated to the point that it is nearly the size of a male's penis and is likewise fully erectile. Astonishingly, females mate and give birth through the long, narrow canal running down the center of this "pseudopenis." During mating it retracts much like a shirt sleeve being pushed up, and during birth it stretches so much that it looks like a water balloon. "From a human perspective, the process can be thought of as giving birth through an unusually large penis," says Frank. [...] Whatever the cause, female masculinization is apparently a very successful strategy for the spotted hyena, which is the most abundant large predator in its range. But this success comes at a cost that is tremendously high for the spotted hyena--and presumably prohibitively high for other species. Notably, giving birth is difficult and dangerous, especially for first-time mothers. The fact that the pseudopenis has such a long, narrow birth canal is enough to make it a poor organ for delivering a baby. But there is the added complication that the end of the pseudopenis cannot stretch enough to accommodate passage of the baby: In a first-time mother, the baby tears its way out. "It's the only time I've ever heard hyenas cry out in pain," notes Frank. Even worse, the umbilical cords are so short that many first-born babies die. At only six-inches long, the umbilical cord is far too short to traverse the foot-long canal down the pseudopenis, which means that either the placenta detaches or the cord breaks before the baby is born. (For comparison, in women the birth canal is only a few inches long and the umbilical cord is a generous foot and a half long.) The longer a hyena's labor, the more likely her baby is to suffocate and be stillborn--and the more likely the mother is to die. In captivity, first-time mothers labor as long as 48 hours and nearly three-quarters of first-born cubs die. Without veterinary help, many of these mothers probably would have died along with their babies; in the wild, many females die at three to four years, the age when hyenas typically first give birth. |
Human sex
If humans are the pinnacle of the Unidentifiable Flying Intelligent Designer's creations, how is it that we have the disadvantage of requiring a member of the opposite sex to reproduce, when lower forms of life --such as bacteria, viruses and protozoa -- are sexless and far more prolific? If they can reproduce by far simpler methods, why can't we?
I would have said that this is a rather daft objection, but given that, reversed, it has been used by creationists as an argument against evolution, I cannot resist including it practically word-for-word in this list. See here for discussion and here for the original usage.
Manatee toenails
Manatee flippers have toenails. Why?!
Marsupial eggshells
Marsupials are mammals, and they give birth to live young. Yet their embryos develop in shelled eggs, from which they hatch inside the mother.
See Selwood (2000): 'Marsupial Egg and Embryo Coats'. Cells Tissues Organs Vol. 166 No. 2, pp. 208–219.
Now, as Selwood notes, this eggshell does seem to be important. But that doesn't explain why it is needed -- after all, placental mammals manage fine without making an eggshell, then hatching from it.
Marsupial infants
Having hatched from their eggs and developed some more, newborn marsupials infants are born from the usual opening, and have to wriggle arduously through their mother's fur to reach the pouch and nourishment. Why are they not born either more fully developed (like placental mammals), or even straight into the pouch?
What is even more strange is that the designer -- working with a fresh slate for each 'kind' of organism -- should choose to use this clearly suboptimal design over and over again, in such diverse creatures as kangaroos, koalas, wombats, numbats, marsupial moles and thylacines. And quolls...
Eastern quolls
Quolls are Australian marsupial carnivores. They are overall rather cat-like, but with mouse-shaped faces. They are, in two words, dead cute. As with other marsupials (see above), baby quolls are tiny pink jellybeans, which have to wriggle through the fur from vaginal opening to pouch. Once there, they attach themselves to a nipple and stay there until ready to leave 'home'. Unlike placental mammals, therefore, nipple use does not rotate among the young.
A female quoll has six teats. Which makes it rather odd that Eastern quolls (Dasyurus viverrinus) give birth to up to 30 young. So the 24 weakest / slowest to the nipples are guaranteed to starve to death.
Having at least three-quarters of your offspring inevitably die, because they can't get at the food you provide them... is good design?
More on the quoll here.
Kangaroo molars
Kangaroos, which are grazers, do not have the high-crowned (hypsodont) molars of cows and horses, nor the continuously-growing molars rabbits etc have. Instead, new molars grow at the back of the jaws and move forward, replacing the worn-out ones which simply drop out. But they cannot do this indefinitely: they get four pairs of molars, and once those are worn out, the animal starves to death.
Platypus teeth
The platypus (Ornithorhynchus anatinus) does not have teeth, but instead crunches up its food between grinding plates on their tongue and palate. What's wrong with teeth? Why does no other critter with similar diets have these grinding plates, if they're so good... and if they're not, why no teeth for the platypus? This is especially odd because young platypuses do have teeth... which do not erupt through the gums! And made even more strange -- in terms of design, at least -- by the fact that there is a fossil platypus, Obdurodon, which did have functioning molars.
Platypus ovaries
As might be expected in a bilaterally symmetrical animal, platypus females have a pair of ovaries. But the one one the right side is poorly developed and does not function: though it produces oocytes (primary egg cells), these do not mature. Unlike birds, which share this single-functioning-ovary feature, the non-functional platypus ovary "does not undergo compensatory growth in any form after the removal of the left ovary."
See Terence J Dawson (1983), Monotremes and Marsupials: the Other Mammals, p.14.
Apoptosis
Apoptosis is a process in the development of an embryo which involves programmed cell death. Cells are formed... only to be destroyed. Now, it's possible that this might be a sensible way to go about making some parts. But for instance, vertebrate distal limbs -- that's your legs and forearms -- have two bones in them, the tibia and fibula, the radius and ulna. That's how they need to end up, how they're designed to be. So why do these two bones start out as a single bone, that then divides into two by the cells dying off? If two bones are required, why not make two bones? That happens elsewhere in the body. Why kill off cells that resources have gone into making? What a waste of materials!
Toothless creatures' foetal teeth
Anteaters and baleen whales do not have, and do not need, teeth. Yet as they develop in the womb, they form teeth, then reabsorb them.
Dolphin embryonic hind limb buds
As they develop, dolphins (and -- an evolutionary prediction -- other cetaceans, I'll bet) start to grow hind limbs, which of course they do not have and do not need once they're born. These are later reabsorbed. So for what intelligent design reason do they have them? See eg: Thewissen et al (2006): 'Developmental basis for hind-limb loss in dolphins and origin of the cetacean bodyplan'. PNAS Vol. 103, No. 22, pp. 8414-8418; Sedmeraet al (1997): 'On the development of Cetacean extremities: Hind limb rudimentation in the Spotted dolphin (Stenella attenuata)', European Journal of Morphology 35(1): 25-30. |
Human embryonic tails
Between four to seven weeks of development, we humans have a tail. It is later reabsorbed. Not only that, but we share with mice (in whose genome they've been found) the same tail-making genes. It appears that there is a separate mechanism controlling the tail's apoptosis (qv), so that the occasional human born with a tail isn't like that because of the reactivation of old genes, but rather because the genes to remove it have malfunctioned. Erm, special genes to remove something we're not supposed to have?
The human coccyx
If a single bone is required, why does the coccyx start as separate ones that just happen to look like little vertebrae, which then fuse into a single lump? Why is there a muscle -- the extensor coccygis -- which would flex these bones, if only they weren't fused -- isn't that rather pointless? And why is the coccyx's development controlled by the same genes that make tails in other mammals?
When a coccyx is longer and its bones not fused, we call that sort of coccyx a 'tail'. Or conversely, a really shortened tail with the remaining bones fused would look different from a coccyx how?
[Further discussion]
Guinea pig tails
Guinea pigs have tails. Just about anyway... for they are so short (reduced?) that they do not extend outside the body.
Peacock tails
The tails of peacocks are so long that the birds (which are a favourite food of tigers) can barely fly. Surely there are less dangerous ways to attract females?
Primate dietary requirement for vitamin C
Apes and humans require vitamin C in their diets... which is rather odd, because most mammals synthesise their own. Yet although we humans cannot; we do have the same gene for this that they do... but it is broken! And it is rendered non-functional by precisely the same mutation in all the great apes. Coincidence? And how loving of the creator to give people without adequate diets scurvy!
Guinea pig dietary requirement for vitamin C
As with apes, guinea pigs also require vitamin C in their diets, and for the same reason: a gene involved in its synthesis is broken. But unlike apes, their gene is rendered inactive by a different mutation from the primate one.
Cat taste
Unlike most mammals, cats are uninterested in, and presumably are unable to taste, substances that are sweet. 'So what', you might say, 'they don't need to'. Well perhaps. But if they don't need to taste sweet things, it is odd that they possess the same requisite genetic machinery for sweet detection that other mammals have... but one of the two receptor genes is broken, rendering it non-functional.
What's more, the exact same deletion and stop codons are found, not just in domestic cats, but also in tigers and cheetahs, which means the designer gave superfluous sweet-taste genes, and then broke them identically, not just to one design, but to several.
See Li et al (2005): 'Pseudogenization of a Sweet-Receptor Gene Accounts for Cats' Indifference toward Sugar'. PLoS Genetics, July 2005.
Grass as a food
All those animals that are 'designed' to eat grass. Yet grass is a terrible food. Why does it contain so much silica, if not to protect itself against... the animals that were designed to eat it...? And it is deficient in minerals, so much so that animals have to migrate for hundreds of miles to get to 'salt licks', and elephants have excavated whole caves in their efforts to get minerals from the rock.
Cellulose digestion
What's more, ungulates can only get the little nutrition they do from grass because of the millions of bacteria and protozoa in their guts that break down the cellulose that makes up the plant cell walls. Enzymes are readily apparent in animals to break down other foodstuffs. Surely the designer could have given plant-eaters an enzyme or two for this for themselves -- after all, 'mere' bacteria can do it!
The Chinese grass carp
In a similar vein, the Chinese grass carp, Ctenopharyngodon idella, grazes on aquatic plants and, during floods, on land vegetation. It has specialised pharyngeal teeth that enable it to break up leaves, and so access the cell contents. So the creator clearly intended it to be able to eat these plants. Yet like most vertebrates, the cellulose itself, and the many unopened cells, pass undigested through the gut. If only it had the appropriate gut bacteria... (Did the intelligent designer just forget the grass carp when he was giving out the bacteria? Well I suppose there are a lot of species, so he can't be expected to remember everything.)
Aphid symbiotic bacteria
Why do aphids need bacteria living inside of them to produce dietary supplements, when a reasonable designer would have given aphids all the biosynthesis capabilities needed to live off of plant sap?
See eg Shigenobu et al (2000), Nature 407, 81-86.
Convoluta flatworm mouths
Flatworms of the species Convoluta roscoffensis are green because their translucent tissues are packed with Platymonas algae. The algae live, grow and die inside the bodies of the worms. Their photosynthetic products are used as food by the worms, and the algae recycle the worms' uric acid waste as food for themselves. The worms' mouths are superfluous and do not function after the larvae hatch: worm plus algae plus sunlight is a self-contained unit. For what divine design purpose do the flatworms have mouths, as other flatworms have?
Animal chlorophyll
And just how useful would it be in times of hardship if any animal could make its own food? Some chlorophyll (or strategically placed algae!) would do it. But only plants have it.
Mayfly mouths
Many groups of insect divide their lifecycles up into a feeding stage -- a caterpillar, for example -- and then an adult stage, whose main job is to find a mate. In many species, though, such as mayflies, that is just about allthey do -- they do not even feed (and hence have a short adult life). And yet these adults have mouthparts -- often reduced -- that serve no purpose.
Mammalian lung ventilation
The mammalian tidal respiratory system. Because of the way it works, mixing fresh air with 'used-up' air, it is not very efficient. Is there a better system available? Sure! Birds have a through-flow system, whereby the incoming air is not mixed with the deoxygenated air. This is not just a bit more efficient, it is in the order of ten times more efficient.
So the Intelligent Designer gave bats (eg pipistrelles) a hugely inferior lung ventilation system to that of birds (eg nightjars)! And used the bird one in kiwis, and the bat one in humans, whales and cheetahs. Go figure.
Echidna spurs
The monotreme echidna ('spiny anteater') males have non-functional and reduced poison spurs on their hind legs. Reduced relative to what? Why, the working version found on the hind legs of males of another creature. And that is... the hedgehog? Porcupine? Nope, the only other egg-laying mammal, the platypus.
Pouchless penguins
The echidnas above lay eggs... and put them straight into their pouches. One might think that if a pouch is a Good Idea™ for an egg-laying thing, that it would save birds having to fanny around with nests. Ah, you might say, but birds have to fly, and having a nestfull of eggs or chicks in a pouch would make flight difficult. Sure... but not for flightless birds!
This is especially relevant for penguins. Penguins, like every other bird, need to keep their eggs warm. Living in the silly places they do, however, means they can't have a nest (made of what -- shaved ice?). Instead, the poor little buggers have to sit the egg on their feet and cover it with a flap of groin skin. When they do this, they can hardly move, and they have to swap it over to other penguins if they want to go and grab a bite to eat, which often involves rolling it along the ice. This is a dangerous way of keeping an egg warm. Imagine how much easier it would be for them to have that flap of skin surrounded with contractile muscles, like a marsupial pouch between its legs. If it was really good at sealing (with glands producing water-resistant mucous?), then the bird could even take the egg with it when it goes swimming for food.
There is no questioning that a better developed pouch would be useful to penguins, given that they try as hard as they can to have one anyway. And, a sealable pouch design was known to the Creator, because he used it in the yapok (water opossum, Chironectes minimus). But... but... the eggs might get broken! So, uh, how about having live young?
Many thanks to Doubting Didymus at IIDB for this item.
Cell organelles
Cell organelles such as mitochondria and chloroplasts have their own DNA, which is inherited separately from the rest of an organisms' genetic material. Why should the code for small elements within each eukaryotic cell be inherited separately and differently from that which forms the rest of the organism in all its intricacy -- the leaves, bone, teeth, eyes, antennae or brains? An odd design -- and the numerous structural and biochemical resemblances between these organelles and existing parasitic bacteria are mere coincidences, of course.
Human limb regeneration
... or rather, our lack of it. If a 'lowly' salamander loses a limb, it can grow another one. It does this by reactivating the genetic instructions for limb formation that, in the embryo, formed the limb first time round. If we are such important creatures to the Creator, why did he not bother to endow us with this ability? Why do mammals in general not have this blatantly useful feature?
Flatfish skulls
| Bony flatfish (order Pleuronectiformes) -- around 500 species including halibut, plaice, sole and turbot -- have a grotesquely twisted skull.If you are a fish and want to hug the contours of the sea bed, there are two ways your body can be flattened. The most obvious is front to back, laying on your tummy, as rays and some sharks are. Sharks are generally already slightly flattened dorsoventrally. Most bony fish, however, tend to be flattened in a vertical direction (higher than they are wide). No surprise to an evolutionary biologist, then, that those bony flatfish that do swim at the bottom are flattened sideways, and lay on their side. The problem with this is that one eye would always be pointing at the sea bed. They solve this by the skull contorting during development, so that one eye migrates to the other side. You will notice though that their mouths are still sideways on. They are cartoon stereotypes of what a mutant should look like. How is this 'intelligent design', rather than design constrained by history, by the materials it started with? |
The human appendix
It has recently emerged (Bollinger et al, 2007) that the appendix is, in fact, a pocket for keeping safe some of the 'good' gut bacteria, in the form of biofilms, so they're not all flushed away if a dose of amoebic dysentery (for instance) comes through. As those authors say:
| Regular shedding and regeneration of biofilms within the appendix would be expected to re-inoculate the large bowel with commensal organisms in the event that the large bowel became infected by a pathogen and was flushed out as a defensive response to that infection. |
Two further considerations:
1. Why do we need 'good' bacteria anyway -- could the Designer not give all the requisite biochemical skills which they perform to the gut wall cells themselves?
and
2. Who designed these pathogens that the gut flushes out (meaning some 'good bacteria' need a special pouch to be retained in)?
See Bollinger et al: 'Biofilms in the large bowel suggest an apparent function of the human vermiform appendix'. Journal of Theoretical Biology (2007), doi:10.1016/j.jtbi.2007.08.032 (in press as of 9 October 2007).
The male urethra
The urethra -- the tube via which urine exits the body -- is a soft tube. And it runs through the prostate, an organ prone to infection and subsequent swelling.
A mechanical engineer, a chemical engineer and a civil engineer were discussing the human body in the pub. "The body was clearly designed by a mechanical engineer... look at all the levers and joints." "No no no, it was obviously designed by a chemist, it's full of amazing chemical reactions!" "I'm sorry", said the civil engineer, "but it was undoubtedly a civil engineer. I've run countless sewage pipes through recreational areas myself..."
The human spine
Bipedal vertebrates usually carry much of the spine roughly horizontally, and balance it with a tail. Equally, a string of cotton reels with spongy cushions between is a good cantilever bridge type design for flexible quadrupedal running. But it's a lousy thing to stand on its end and withstand the compression strains of vertical bipedalism. Compression strains are best absorbed by pillars. If you want the pillars to be flexible, you put joints in them. In biology, we have examples called 'legs'.
And why thread so important a feature as the spinal cord through the middle of this, where disc damage can cause anything from pain to paralysis?
The spine's 'design' thus results in back pain which causes over 149 million annual days off work in the U.S. alone, costing $50 to $100 billion in lost wages and medical costs, 80% of people being affected by back pain at some point in their lives, backache during pregnancy (extra weight pulling in an out-and-down direction it can't happily support), and why you find, if you've ever 'slipped' (herniated) a disc, that about the only comfortable position is on all fours.
The human knee
Ask any long-distance runner or basketball player. Or even Morris dancer.
The human jaw
... is too small for the number of teeth it holds, hence impacted wisdom teeth (third molars).
Useless beetle wings
Numerous beetle species are flightless, such as darkling beetles (Tenebrionidae, eg Eleodes species), the Kauai flightless stag beetle (Apterocyclus honoluluensis), and many weevils (Curculionidae, eg the Japanese weevilPseudocneorhinus bifasciatus). Darkling beetles, for instance, are ground-dwelling and feed on decaying vegetation, such as dead leaves and rotting wood. Females lay their eggs in soil, the larvae hatch, mature and pupate in soil, and the adult beetles emerge from -- you've guessed it, the soil.
Like most beetles, they have wings... but these are sealed in beneath fused wing covers (elytra), and so the beetles are flightless. For darklings, the fused elytra help conserve water; for others they are a better protection for the abdomen. Wings are obviously not needed for flight for ground-dwelling beetles. The question is, why is the shell on their backs made of wing covers, and why are there (often greatly reduced) wings beneath them? Wings that cannot work on creatures that do not need wings at all?!
Halteres
Instead of the two pairs of wings that most flying insects have, flies (Diptera) have one pair, and instead of the second pair, they have a pair of tiny halteres ('balancing organs'). Halteres are a neat piece of kit. Many flies can perform amazing aerial acrobatics: they can hover, rotate on their own axis, fly through spaces little wider than their wingspan, and even fly backwards. All these abilities are aided by the halteres, which act like tiny gyroscopes. The sensory organs at the base of each haltere form three groups at right angles to each other, which allows the fly to tell how fast it is flying and turning, and whether it is being blown off course.
Halteres are, then, very well designed for this purpose. And yet... remember where they are located? There is a mutation in flies (best studied in Drosophila melanogaster fruitflies) which 'switches on' the homeobox Ultrabithorax (UBX) gene. Guess what? The halteres grow into a second pair of wings. If halteres were balancing organs, specifically designed for that job, how can they become wings -- that is, things designed for a different purpose? Surely it's not because that's what the used to be...?
Flightless bird wings
Maybe some species use them for something else, but kiwis (Apteryx, four separate species) barely have wings. Barely being the point.
Booby nests
As is well known, birds generally make nests. Well, there's a bird called the blue-footed booby, whose females lay their eggs on bare rock and build no nest. Yet the male still collects nesting materials and presents them to the female during courtship, just as other species that actually build nests do.
Gannet nostrils
Birds of the family Sulidae, the boobies and gannets, are diving birds, plunging from height into the water. And one of their adaptations to this is that they lack external nostrils. This makes sense: the water would otherwise get shoved up their noses on impact.
So is this intelligent design? Not exactly. For though they lack external nostrils, they have everything else that constitutes nasal airways inside their beaks -- the septum, choana etc -- it's just that the nostrils are sealed off at the outside. Having nasal airways that cannot work (since they are blind-ended) is pretty pointless design. Why bother having them at all?
See J B Nelson (1978): The Sulidae: Gannets and Boobies. Aberdeen University Study Series 154, Oxford University Press. Many thanks to Urvogel Reverie at IIDB for the reference.
External testicles
Mammalian testes form inside the body, and then have to pass out through the abdominal wall to the scrotum so they can be at a more conducive temperature for sperm formation. Not only is that odd (why can't sperm be made at body temperature?), but the process leaves a weak spot in the muscle wall. This 'inguinal ring' is liable to herniate, which both obstructs or strangulates the bowel and stifles blood flow to the testicles.
Also, testicular temperature regulation requires a huge investment of musculature and blood flow. Interior testicles would be much more efficient and protected to boot (no pun intended).
The genetic code
DNA has a remarkable copying fidelity... yet mutations -- errors -- are far from rare. If the Good Lord wanted all his creations to be separate, immutable kinds, all he had to do was make the copying mechanism flawless. Meiotic recombination and outcrossing (sex) would still make different individuals. Hey presto -- no evolution. But the system is flawed... so the designer must... want evolution?
Even mere mortal Francis Crick, co-discoverer of DNA's structure with James Watson, proposed a more efficient and robust 'comma-free' code than the real one that living things use, before the real one was known. Crick's code design avoids frameshift mutations and has precisely as many states as there are amino acids to be coded for. Rather more optimal... and no known life uses it.
'Junk' DNA
Most organisms, humans included, contain in every cell vast quantity of 'junk' DNA: pseudogenes, introns, transposons, retrotransposons, etc, which does little for its owner except get itself copied. Pseudogenes, for instance, are chunks of DNA which have a resemblance to known genes that is too improbable to be coincidence, but which are, for instance, not prefaced with a 'start' codon. Thus the DNA-to-RNA transcription system doesn't know that 'here is a gene to be expressed'.
This is not just an idle observation: a vast amount of human DNA is junk. For example, the human Alu sequences are repeated some million or so times, and this one family alone accounts for about 5% of our DNA. (However, Alu might have a use after all, but it would appear that this use developed after the Alu's appeared, because most living things do just fine without them.) In Drosophila fruitflies, 40% of the genome is taken up by three sets of so-called 'satellite DNA': pieces just seven 'letters' long, with no 'meaning', repeated eleven million, 3.6 million and 3.6 million times.
Using more materials than are needed is not good design.
(It's worth noting that junk DNA, as I'm using the term here, is not synonymous with non-coding DNA. There is plenty of genetic material that, while not coding for a protein, is involved in gene regulation and expression. But there is still masses of genuine junk that does not, and cannot, do anything at all. Indeed, much of this real junk -- the pseudogenes -- would code for a protein, if only the code were not broken in some way.)
Genes for non-existent features
Birds do not have teeth. But birds have genes, normally non-functioning, for making teeth.
Birds do not have full fibulas (the second, smaller lower leg bone); it is that little splinty thing that you find down the side of a chicken drumstick. And their tarsals (ankle bones) are fused into a single lump and to the other leg bone, the tibia, forming the main part of the drumstick, the tibiotarsus. But birds have genes, normally non-functioning, for making complete fibulas with separate tarsals .
Horses have a single toe on each leg. But horses have genes, normally non-functioning, for extra toes.
What are genes for making these things doing in creatures that don't need them, don't normally have them... and if separately designed, never have had them?
Hollow ostrich bones
Ostriches, which are not known for their flying abilities, have hollow bones. They share this feature with flighted birds (except in their legs, where strength is now a survival attribute that natural selection can operate upon). Being ground-based, such weight-reduction does not seem appropriate... but if this is a useful feature, why do other land animals not have it?
Solid bat bones
Bats, which are well known for their flying abilities, share with terrestrial mammals -- from elephant to mouse -- their usual solid bone structure. One has to wonder why the designer did not give bats the hollow, weight-reducing, bone structure design he used throughout birds (whether appropriate or not). Conversely, if solid bones are better for a flying thing, why do no flying birds have this feature?
Greenland shark eyes
Sharks hunt, up close at least, by sight. Greenland sharks (Somniosus microcephalus), however, are nearly all blind, due to the presence of parasitic copepods (a subclass of crustaceans) that feed on the skin of their eyes. The sharks benefit because the copepods are bioluminous, and by their wriggling attract other fish which the sharks then snap up. But where is the intelligent design in such a complex set-up, and why does the shark need eyes if they are going to be parasitised to blindness as part of the design? There are other more straightforward ways to lure fish with a bait, as anglerfish (order Lophiiformes -- about 210 different species of them) show, rather than first having eyes, then having them go blind.
Lesbian lizards
Cnemidophorus whiptail lizards are parthenogenic -- they are all females, no males. But it's been found that an individual's fertility increases when another female acts like a male and attempts to copulate with it (they apparently do this quite regularly and quite unprovoked by experimenters, by the way). These lizards' nearest relatives -- oh okay, the ones most similar to them in geography, genetics, anatomy and biochemistry -- are sexual species. And the hormones for reproduction in these others are stimulated by sexual behaviour. So it's no surprise -- to 'evolutionists' -- that although Cnemidophorus are parthenogenic, simulated sexual behaviour increases fertility. But it's a bit of an odd thing to design.
- Crews and Young (1991): 'Pseudocopulation in nature in a unisexual whiptail lizard', Animal Behaviour 42: 512-514.
- Crews and Fitzgerald (1980): ' "Sexual" behavior in parthenogenetic lizards (Cnemidophorus)', Proceedings of the National Academy of Science 77: 499-502.
Gastropod development
As they develop, all gastropod mollusc larvae do a 90 to 180 degree twist, so that their mantle, kidney opening and anus are sticking out over their heads. Which seems rather odd design, but okay... The really stupid design is the fact that slugs (subclass Pulmonata) and sea slugs (subclass Opisthobranchia) then do an untwist, and straighten their bodies out again.
Goose bumps
Since humans (especially women) generally have little body hair, it is pointless having the same system of muscles (the arrectores pilorum) and sympathetic nerves which in most mammals raises the hairs in response cold or fear. Nevertheless, we get goose bumps (cutis anserina). What's more, if our skin is meant to be mostly bare, why do we have the tiny ineffectual hairs (and separate muscles and nerves for them) at all?
Human grasping reflex
The grasping reflex in human babies would only seem to make sense if we used to have rather more body hair, like other primates. It appears a rather pointless design otherwise.
Sex
Sexual reproduction is not anywhere near '100%': most copulation is inefficient and fails to produce viable offspring. Why are millions of sperm required? Good design, or merely adaptive?
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