Physical Improvements

Anders Sandberg (
Sat, 24 Aug 1996 20:34:53 +0200 (MET DST)

[As usual, I would like to hear suggestions for improvements of this
document. It resides at]

Physical Improvements of Humans

By Anders Sandberg

Based on the discussions on, August 1996. I have stolen
ideas and some sentences from the participants, which I hereby acknowledge.

This page is devoted to modifications of the human body that are mainly
surgical, chemical and genetic; bionics and genetic engineering have their
own pages.

Many of these ideas are general improvements of bugs or atavisms in our
body, while some are outright changes. While some are likely to be popular
among all humans (like production of vitamin C and improved organ
suspension) others (like becoming amphibious or furry) will probably be used
by only some people.


There are many possibilities for strengthening the skeleton, but it is
important to keep the lightness and avoid making it too brittle (metals are
too heavy). One idea is to use buckytubes or diamond composites instead of
calcium phosphate crystals as the hard component of the bones.

Arms and Hands

Hands are definitely the area (beside the brain) where people have the most

Generally, many would like to extend their capabilities with extra opposable
fingers. At the same time, while the thumb is strong and dextrous, it is
rather slow and not suitable for fine manipulation. Having fingers of
different sizes is useful, and many would like to have longer fingers.

The formation of the fingers are due to a gradient of morphogens, which
induces the different changes. By influencing it, we can get more fingers
and quite possibly two thumbs. It seems likely that the shape, number of
joints and strength of the fingers can be changed this way.

Adding more fingers might decrease motoric and sensory acuity if the cortex
is not extended, but the brain is believed to have quite a bit of reserve
capacity in this area.

Adding two extra arms is a popular idea, although this would require some
rather complex bone restructuring in the torso to attach them. A more
radical idea would be two tentacles (octopus-style) extending at the
shoulders (this would add a new way to manipulate objects)

The medial nerve and the tendons for the thumb go through the carpal tunnel,
which is clearly limiting and often gets into trouble. They should be


Many people complain that the knees are easily damaged; they are actually
quite optimal, but might profit from a few more ligaments.

The feet can be redesigned to prehensile feet, although that would limit our
ability to walk long distances or run very fast in exchange for increased

One radical possibility would be to add an extra pair of legs. This is
complex, but one idea is to add an extra hinge point to the torso so that
the arms and head could be raised (much like a centaur); we could walk on
all fours while using our hands normally. This could be combined with
widening the pelvic arc, and perhaps with making the first pair of feet
prehensible (the arms are used for dextrous manipulation, the forefeet for
manipulation requiring strength).

Altering the proportions of fast-twitch, slow-twitch muscle fibers might be
desirable for some people; muscle cells do not divide, but can
enlarge/shrink depending on use. It might be desirable to add the option of
some regrowth, especially to deal with accidents and wounds.


The main problem with the torso is the spine - it is easily overloaded and
damaged. One possibility would be to add a few short ribs to the lower back
to attach tendons, improving overall strength and resilency, but decreasing
the twisting ability. It is probably likely that it could be modified in
other ways to work well with our new ecological niche as seat-dwellers (this
could be combined with modifications of gluteus maximus).

One idea is to suspend internal organs from the skeletal system, perhaps
using tendons, instead of letting them lie on diaphragm. This would prevent
many forms of hernia.

Gastro-Intestinal Tract

The symbiotic intestinal flora might be improved or made "smarter", for
example by adding genetically designed versions (overall, our entire
microflora could be improved, for example to produce clean or pleasant

One possibility would be to modify the urinary system to output its waste
into the GIT, but caution has to be taken to limit the risk of infection.

Circulatory System

Since we are bipedal, our circulatory system has to work much harder to pump
blood vertically. It might be a good idea to add an extra heart or several
"helper hearts", perhaps based on the peristaltic hearts of insects, along
the aorta or in the legs.

Adrenaline thickens the blood, it becomes more likely to clot; very sensible
in a natural environment, but downright deadly in a stressful modern city.
Unlinking the fibrinogenic system from adrenaline control would definitely
lower the incidence of cardiovascular disease.


The human breathing system has some drawbacks, primarily the risk of choking
on food. Ideally breathing/speaking would be done through another orfice, or
at least there would be a spare opening that could be used in desperate
situations or for integration with scuba gear and similar technological

Most air in the lungs is rather stale and is not vented with each normal
breath, but this is a minor problem since the primary purpose of the lungs
is to went carbon dioxide instead of absorbing oxygen (which is very
plentiful). A uniflow system would be much smaller, but would loose heat and
water faster than our current countercurrent system.

Aquatic breathing is a classic idea. Making human amphibious or wholly
aquatic is more complex than modifying the breathing system, it would be a
good idea to add a thicker warming layer of fat beneath the skin, make the
arms and legs more suitable for swimming, fill the ears with water to enable
underwater hearing and modify the eyes (for example by adding clear
nicticating membranes).

One possibility would be reserve air storage, for example by improved red
blood cells and myoglobin. But the main problem is getting rid of carbon


Built-in contraceptives are a quite popular idea; some might be interested
in removing menstruation, PMS and menopause entirely. Ideally, ovulation
(and ejaculation) would be under voluntary control.

The female pelvic girdle is a bottleneck, both due to our large heads (see
the head section for some ideas) and our upright stance. It is surprisingly
flexible, but might still be improved judging from the number of cesarian
sections and deaths at birth in general. A radical solution would be to use
a pouch instead, like kangaroos. This would allow the head to grow without
any traumas, and allow men to bear children too (assuming the embryo grows
inside the mother, then leaves and climbs into the pouch of the father or
mother). Some psychologists have suggested that this would reduce birth
trauma a lot and enhance mother(father)-child bonding.

Some people might like genital taste buds and other improvements in
innervation. Since the taste cortex is very close to the primary sensory
cortex of the tounge, it appears likely that genital taste buds could be
implemented and linked to suitable cortical regions by piggy-backing on the
normal sensory pathways (most likely the taste sensations will be different
from oral taste). Erogenous zones are apparently partially culturally
dependent and often individual, but it appears likely that there are some
neural pathways that could be added to create new erogenous zones (or remove

Some find it unaesthetic to place the urinary tract in or close to the
sexual organ, and would like another solution (like emitting urine into the
lower intestine)


We are adapted to a diet of a projectile-predator on the East African
savannah, not to living in a techno-agricultural niche. Our metabolism can
definitely be modified to fit our current lifestyle better, and avoid many
common problems (such as cholesterol plaques; predators manage this nicely,
but as omnivores we have problems with excessive intake).

Make weight and metabolic setpoints more easily changed; some peoples have
problems in storing surplus food, so that the are more susceptible to
malnutrition, while others tend to store too much fat and develop diabetes
and heart disease.

Humans are among the few mammals that cannot manufacture vitamin C. Adding
this capability would appear very simple, and it might have useful effects
as an antioxidant and immune-enhancer.


Pigment levels should ideally be easier to control, so that it would become
darker to avoid sunburn before it occurs.

The amount of hair that appears is apparently genetically determined
(although beard growth is positively correlated to testosterone levels). It
might be desirable to find ways to increase/decrease the amount of hair. Fur
is a distinct possibility, together with adding patterns to it (this might
be done to the skin too, creating "tigers" or "leopards").

An increase in sensitivity in some areas is probably desirable, and quite
probably pleasurable.


The human head is a evolutionary bottleneck; making it any bigger would
complicate birth enormously, and probably incur a greater chance of brain
damage. One possibility would be to influence bone and brain growth so that
more development can occur outside of the mother's body. There are still
some limits to the size of the head, especially since it has to balance on
the spinal column and the neck muscles.

The skull is a good protection for the brain, but maybe not optimal.
Especially intracranial hemmorages are very dangerous, hard to detect in
time and mostly due to badly arranged blood vessels. Ideally the numerous
small and easily damaged veins between the skull and brain should be made
more flexible, removed or replaced with reinforced larger veins.

Update the sinuses to belong on an upright biped - our noses tend to clog
instead of drain.

Human teeth are problematic, due to our long lifespans and our tendency to
eat food that are bad for them. Inducing the growth of several sets of teeth
instead of just the milk- and adult-teeth seems to be a good idea (unless
one want to replace them with wholly artificial systems a la Jaws or use
resilient ceramics).

Remove the vomero-nasal organ (VNO) to become independent of pheromones.
This will likely make a person less likely to become romantically involved
with others or react strongly to the body odors of people, but might suit
those who want to keep their emotions entirely under their own control.


Adding ultraviolet vision is possible, since our receptors can detect it
(partially by fluoroscence) but the lens absorbs it; by replacing the lens
UV-vision becomes possible. Unfortunately this increases the risk for
retinal damage, and there would be some problems with chromatic aberration
(maybe we could develop a double lens system to fix this).

Infrared sight is hard to do well, since the eye would only be able to see
objects warmer than itself.

One idea would be a pair of extra eyes specialized for UV or IR vision
(perhaps like the heat-sensitive pits of certain snakes), and another would
be to add nicticating membrances to limit the part of spectrum we look at.
This could also be protective and useful for aquatic living.

Brain and Nervous System

Humans are easily addicted by pleasurable stimuli. It might be a good idea
to add a taste-flip, so that a repeated stimuli after a while is not as
pleasurable (this would have to work around the fact that most addictive
drugs influence the mesolimbic dopamine system and nucleus accumbens; the
mental interpretation of this would have to be possibly reversed by
introducing habituating interneurons). This would be similar to how boredom
makes repeated behaviors slightly unpleasant, keeping us active.

The chemical senses of the brain are subtle, and are often able to detect
quite well if some nutrients or chemicals are lacking in the body. These
senses might be strengthened and made more conscious (as sometimes happens
during pregnancy), which no doubt would improve healthy eating. In some
diseases smell becomes more acute, which shows that it is possible to
enhance senses in a biological way.

In the same way, it might be desirable to be able to control the strength of
sensory stimuli, to avoid being overwhelmed. This could involve the ability
to "close one's ears" and suppress pain (pain is an important signal that
something is wrong, but should not incapacitate us)-

Sleep is important (probably to integrate memories during REM sleep and to
let the immune system function well), but should be easier to control. Since
it is possible to train oneself to become an "efficient sleeper", it is
likely that it could be speeded up biologically. The ability to temporarily
suppress sleep is desirable, although long-term effects are probably rather

The "fight-or-flight" stress response tends to "white-out" higher mental
functions and replace them with instinctive reactions - very efficient in a
dangerous natural setting, but less useful in a technological world where
dangers seldom can be avoided by instinct. Ted Sturgeon suggested that the
response would be rewired so that the higher functions become more active
and speed up under serious stress. This would require some rather complex
rewiring of the brainstem, but is probably feasible (for example, the
noradrenergic neurons of the locus ceruleus have a generally activating
effect on the whole of the brain, and are linked to this response).

There are many subtle errors in normal human cognition, which cause various
problems in the modern world. For example, we tend to mix up implication
with equivalence, judge risks in a very irrational manner (more people are
afraid of flying than of driving) and make incorrect generalizations. If
deductive/inductive reasoning could be instinctively learned during early
maturation just like language, or these errors corrected, people would
become less likely to fall into logical traps or irrationality.

"Temporal Lobe Personality" is a term sometimes used to describe some
people, who have increased activity in their temporal lobes: sexual drive is
suppressed, paranoia, they tend to become almost monomaniac, extremely
obsessed with details of the work and often have grand visions. Apparently
both Dostoyevsky and van Gogh suffered from this condition. It would be
useful if the more positive symptoms of TLP could be replicated and
voluntarily controlled.

Our bad memory is a common complaint. While long-term memory is very good,
we are not as good at retrieving necessary information (this can be
trained). And short-term memory can only handle 7+-2 chunks; if this could
be extended we might become much better at handling several trains of
thought at once.

Immune System

The immune system is excellent at fighting intruders and antigens, but tends
to overreact, especially in places of high living standard where there are
fewer dangers (the mast cells, which normally fight parasites seem to cause
allergies when they are "out of work"). Ideally, its level should be more
easily controllable, so that it could be kept at a safe level most of the
time, and increased when shifting environment. This could be combined with
the possibility of decreasing its attacks against certain antigens (but not
all) to enable implants or some forms of surgery.

Hormone System

Our emotions are strongly influenced by hormone levels, which tend to swing
out of control during adolescence or in some situations. It might be
desirable to have conscious control of how much hormones are released, or to
make the brain less susceptible to their influence.

Decline in hormone levels due to aging should naturally be lessened; this is
actually one possible origin of many aging signs and diseases.

Aging and Development

Slowing aging is high on almost everyone's wishlist.

In our society, we would need a longer maturation time, ideally with no
fixed end. One possibility is to make maturation and aging slow down more
and more, so that everyone eventually reaches a steady state corresponding
to the 20's (which are optimal in many ways).

"Youthful idealism" might be partially hormonal, a way to make young males
restless and leave the tribe to found new tribes. This apparently declines
in most people as they age and become settled, but it might be possible to
extend it (an idealism supplement?), which would probably be very healthy to
do from time to time to prevent mental aging.

Anders Sandberg Towards Ascension!
GCS/M/S/O d++ -p+ c++++ !l u+ e++ m++ s+/+ n--- h+/* f+ g+ w++ t+ r+ !y