evolutionary adaptation


According to a recent study by Professor Cedar, Vaporeon has the capability undergo variant evolutions tied to its environment.

This is speculated to be due to the highly volatile nature of Eevee DNA and the evolutionary tactic of extreme adaptability all Eevee possess. To adapt expertly to climate and environment upon evolution, the pre-evolution Eevee will adopt aspects of other residing species of pokemon, ensuring an incredibly high survival rate.

The standard Vaporeon variant occurs if the Eevee has not resided in a particular environment for an extended time, or in heavily populated human city centres.


With a tail that can be long as its body, the Thresher Shark attacks its prey with violent whip like motions.

This behaviour has been suspected by researchers, but only recently has it been caught on film. The tail is used to stun, maim or even kill the prey, with the shock-wave created by the momentum also stunning surrounding fish.

It is thought to be an evolutionary adaptation as these sharks hunt mainly smaller fish such as sardines. This makes the whip mechanism much more efficient at catching multiple fish with a single blow, as opposed to one fish at a time the shark would tend to catch with its jaws.

The tail was caught moving at up to 80 km/h, spontaneously heating and even boiling small areas of water near the very tip of the tail due to the extreme forces involved. 


Have you ever heard the tale of the runaway ✨magical✨unicorn phallus? Yeah, me neither. I also never heard of these Bipes aka Mexican Mole Lizards until my recent trip to Baja ~ thank you 🙏 @islandsseas . Another case of truth is stranger than fiction: due to their secretive lifestyle little is understood of these unbelievably cool creatures. Found only in Mexico, these unique reptiles use their forelegs to burrow through soil like a mole. The hind legs have completely disappeared!
Why are they Pepto-Bismol pink?! What is the evolutionary advantage of this adaptation?
Do they pick up carotenoids in their diet like flamingoes? So many ’?????????????’

#islandsandseas2017 #Bipes #amphisbaenia #curiosity #lizard #discovery #pink (at Baja California, Mexico)

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even the whole “criticizing women for having wrinkles is bad but you need to moisturize, if you don’t your skin will break and you’ll bleed out and been in pain and get infections and die. moisturizers is an adaptation humans developed to survive” thing is so ridiculous. 

Like yeah, moisturizing is good for your skin, and everyone can benefit from it, but you won’t die, and the majority of people wont even develop skin that dry that it cracks open even if they never moisturize. If ur skin is literally breaking open when you move and you’re getting constant skin infections… sounds like u need a doctor asap because that is not normal, even for dry skin. That sounds like a pretty serious skin disease 

the moisturizer as an evolutionary adaption was the cherry on top of this discourse though

.@soft-galaxies: this is really interesting to think about like… one of their four brain lobes focuses on music as a separate component from regular conversational/non-musical noises (i imagine there’s something you could do w/ their brains vs how they can survive in non-ferenginar environments with so much auditory stimulus, also quark is canonically just a loud person so he’s obviously not modulating himself, generally his whole family is loud besides rom i guess)

Brilliant headcanon about Ferengi using a separate auditory process for music.

like you’d imagine a people who are canonically sensitive to noises and sounds most other humanoids can’t hear would be softspoken but they seem to be loud as a rule, and tv handwavey they don’t speak any more quietly than other humanoids they encounter… they can prob hear music at levels non-ferengi can’t hear but might also just be able to tolerate it at regular non-ferengi levels (e.g. nog listening to klingon opera) without pain, so low volumes might not be a thing

The handwaveyness of the show can be so frustrating! Quark is canonically capable of hearing Odo sloshing around upstairs, but he works in an extremely noisy environment with no apparent ill effects. Ah well. I do have a few possibilities in mind:

1) auditory desensitization as an evolutionary adaptation, selectively bred into well-to-do families whose children were expected to do interstellar business (not that plausible and rather boring);

2) hearing dampeners, perhaps integrated into the universal translator (more plausible, but still boring)

3) selective hearing loss after a certain decibel level has been reached - in essence, Ferengi having the opposite hearing range of a human. The quieter an environment, the clearer it would sound to a Ferengi; louder than 65 db or so, certain auditory receptors might shut themselves down defensively. (my personal favorite)

ALSO, all Ferengi are synesthetes to some degree or other and nobody can convince me otherwise.

as for genres, completely unrelated to xenobiology headcanons, i tend to associate more overproduced pop/hip-hop/r&b with quark (things for dancing, movement, grinding… versatile songs), rom with acoustic n gentle genres, nog with experimental ambient, electronica instrumentals (supported by that one ds9 books excerpt about nog enjoying atonal stuff)… i’d imagine there’s a vast amount of stuff b/c competition in a capitalist industry etc.

I also imagine that certain individuals (coughBruntcough) would be uncomfortably into ASMR.

Headcanon that as an evolutionary adaptation to low fertility rates, male elves have much stronger paternal instincts than humans. They will often start nesting and fussing over a pregnant mate before either of them have any idea she’s pregnant, and same sex couples will nest if they have a close friend or sister that is pregnant. Female elves barely notice the fussing because they’ve adapted to the highly tuned empathy a male elf has for a pregnant mate, but if the pregnant mate is human it may drive her batty. When the couple is especially close, the male might even suffer Couvade syndrome.

Just Stop Thinking About It

by Samsaran

Yeah, sure. If it was really that simple. How do you stop thinking about it? Can it be done? Sure it can be done. Believe it or not our thoughts are under the control of our will and all we have to do is to use our will to put the troubling thought out of our mind. 

Some of these anxious or sad thoughts repeat themselves. Over and over. The same worrisome thoughts. But why? Why does our mind do this to us? 

Well, what makes humans unique is our ability to project a possible future. That one evolutionary development has allowed us to spread over the entire Earth from the equator to the Arctic and from the desert to the rainforest. 

However useful this ability is it is also a source of great trouble. Our mental time machine will sometimes get stuck on repeat. Then an evolutionary adaptation meant to increase our chances of survival works against us. The repetitive negative thoughts cause anxiety or depression.

This is one of the things the path of Buddhism is designed to control.


Originally published on social media on January 26, 2013, in apropos of David Mamet’s essay “Gun Laws and the Fools of Chelm” in that week’s issue of Newsweek.

Republished whenever there is another gun massacre.

My death is not only inevitable, it is also imminent.

No, I have neither been diagnosed with a lethal ailment and given minutes to live, nor am I contemplating suicide once I am done putting this down. I merely mean that my life is a mere flash in the two million or so years in which humanity has walked the earth.

Seen in the perspective of that time frame, the end of my life is, in fact, coming very soon – whenever in my life it may choose to arrive. I might as well accept it.

I think about that whenever the topic of gun control comes up… especially when a Czar of American Letters™ like David Mamet picks up the quill to write a barn-burning opinion piece (like that on the cover of this week’s Newsweek) in which he insists that the right to bear arms is an essential component to society; both in that it insures protection against the corrupt depredations of an increasingly intrusive government, as well as in that it is an essential prophylactic against incivility. In Mamet’s philosophy, no one dares to be an aggressor in a society in which every man, woman, and child is given the inalienable right to carry guns.

In short: mutually assured destruction is the best insurance of our right to life. In the macro: should the government overstep, an armed populace will rise to pull it down. In the micro: if you kill, you will be killed.

Mamet’s argument is lucid, consistent, and takes its cues from his – and many other intelligent people’s – interpretation of the frame of reference and aims of the Founding Fathers. It does not surprise me that many whom I consider to be level-headed intellects feel as Mamet does: that an individual is the best and only person to decide how to defend themselves, and that, in this world, an individual can only properly accomplish that goal in possession of a firearm.

Still…reading Mamet’s piece, I could not help but be struck by the preening, hypermasculine worship of conflict implicit in his every sentence. The bedrock conviction that the natural state of humanity is ideological crisis which will erupt into violence at any moment is implicit in his thesis, as well as his beliefs about the role of government, and the individual, in society.

I suppose this should not come as a surprise from Mamet. His work, from the sacred, Glengarry Glen Ross, to the profane – his martial arts film Redbelt and his television series The Unit – range from what is essentially a Valentine to the poetry of emotional abuse to sustained explorations of the ability to enforce one’s mark in combat against aggressors in a world that is viciously opposed to mutual understanding.

To live in the world expressed by Mamet – and, to some degree, to live in the world of most who believe in the socially sanctioned ability to take a life when necessary – is to live in (to borrow and recontextualize a phrase from Carl Sagan) a “demon-haunted world.” It is a prison: a maze in which predators lurk behind every corner and meanness of the soul is either prime motivator or inevitable outcome.

The Founding Fathers must have believed in this world, being as they flagged the right to bear arms in a language as carefully considered as the right to life, liberty, and the pursuit of happiness… and, again, it makes situational sense: they had been oppressed by a totalitarian monarchy and were surrounded by natives who were – understandably – hostile to their genocidal designs on their ancestral homeland.

All of which raises the more important question: when does humanity evolve from the right to bear arms to the right not to?

The study of violence in television – a topic concomitant with issues relating to guns – has yielded a phrase which has bounced in my head since I first encountered it: “mean world syndrome.” The concept is simple: the depiction of violence in popular culture may or may not incite actual violence, but it almost certainly creates the indelible – and vastly exaggerated – impression in viewers that the world is a nasty, brutish place in which violence is not only an acceptable means by which to resolve conflict, but also a complete inevitability.

The belief in a mean world may be profitable for gun manufacturers, but I believe it is a cancer of the soul and an impediment to evolution.

Evolution is a difficult proposition, just as “Thou shalt not kill” is a difficult admonition to follow – especially when others want what you have and have no moral barriers to its acquisition. It is harder to reason than to kill, it is harder to compromise than to kill, it is  harder to exercise empathy than to kill, it is harder to persuade, to forgive, to make a fearless moral inventory of our own wrongs, and to leave others to do the same and see the error of their own ways, than to kill.

It is – admittedly – harder to accomplish pretty much anything without the threat of a reckoning than it is to swing a big stick; and yet, over and over, since the evolution of consciousness, the prohibition of murder continues to be the central tenet of human spiritual and ethical growth. I believe this to be an evolutionary adaptation – a call across the eons telling us that the next step in our development as a species is collaboration and nonviolence.

In spiritual terms, the hard simplicity of the statement “Thou shalt not kill” makes its challenge frighteningly clear. It does not say, “Thou shalt not kill save for cases of home invasion” or “Thou shalt not kill except for when your way of life is being threatened by a formerly democratic government that has really gotten way too autocratic for its britches” and it sure as shekels doesn’t say, “Thou shalt not kill save for in the case of an organized state militia.”

For all the embellishments that human beings put in their spiritual traditions – usually designed to tell others how to live their lives in stultifying, homogeneous obedience and keep out undesirables – it is surprising how often the prohibition of murder shows up. The seeds of virtue are programmed to survive the death of the individual: “Thou shalt not kill” – in all of its forms, across secular and spiritual thought – keeps outliving people, democracies and dictatorships.

That is evolution at work.

Evolution is difficult and inconvenient to expediency. However, as I have been blessed with the luxury of living in what is – arguably – a democracy in which my participation is still allowed, of the opportunity to make a living in my chosen field, of a surfeit of creature comforts and technological expediency, of a preponderance of like-minded individuals who share my faith in God and my reliance on a number of societal systems designed to further my way of life – usually at the expense of others – I believe that I have a duty to make my life difficult in, at the very least, some minuscule but relevant way.

Chris Hedges famously titled one of his books “War Is a Force That Gives Us Meaning.” His argument is that both the perception and reality of never-ending battle instills in human beings a sense of purpose. As long as there is someone or something to oppose, the soul is filled with the comforting tonic of simplicity: don’t worry about empathy, reason, the truth that all humans are genetically identical, or the underlying unity of world religion and ethics, shoot to kill. Indulge your need for violent conquest and all the fuss and muss of worldly life becomes a distant memory. There’s an addictive satisfaction and perverse joy in that clarity.

The bearing of arms, and the perception of it as a right is – to me – a vestige of a primal addiction to violence, and the anodyne ease of a life led in Manichean opposition: an expression of the spirit-destroying contradiction that to be alive and free is to be on constant alert for coming war. To be armed is to never lose sight of the possibility that at any time we may be called upon to reassert our triumphant masculinity through the application of lethal force.

I believe that finding a way of life that does not automatically see in strangers the threat of extinction – that takes kindness, tolerance and collaboration as the first assumption of human coexistence – is both a Christian and Darwinian ideal: a natural continuation of the rise of consciousness. I refuse to be a walking deterrent – just as I refuse to be a talking inciter – of violence.

I believe that there is an evolutionary imperative – expressed across a majority of spiritual and secular traditions – for the prohibition of murder under any circumstance. I aspire to live in a society where fear of the other is not understood as the baseline, and feel duty-bound to that aspiration because the accident of my birth in the wealthiest and freest nation on the planet affords me the privilege to strive for that ideal.  

I believe that the responsibility that accompanies the largely unearned rewards of my privilege – and that of almost every other American – is the exploration of a way of life in which that bounty is no longer earned through violence or exploitation.

I have made peace with the inevitability of my own death. Statistically, the greatest likelihood is that the end of my life will come as a result of heart disease brought about by the excessive consumption of processed foods.

Even in our gun-loving, violence-obsessed, perpetually-in-Defcon-1 United States of America, the possibility of my dying as a result of a violent incident involving firearms – even one involving terrorists carrying firearms – is lower than an automobile accident, plane crash, or lightning strike. So I will not carry a gun in expectation of the one-man war that my very way of life has already conspired to prevent.

I will use my freedom to employ words, actions, and ideas to convince others that to strap on a cold reminder of the ability to take life is not a freeing act, but a bondage to a way of life that must be stopped…

And if I’m shot by a terrorist, or a jackbooted foot-soldier of a totalitarian regime – or even a common criminal?

Forgive them.

Or don’t. I won’t care. I’ll be dead… and the life of my killers, and whatever they stood for that was so important that it required my extinction, will end just as quickly, cosmically speaking, as mine.

I refuse my right to bear arms because I prefer to advocate for my right not to.

I refuse my right to bear arms because I believe that to be the truest expression of the privilege for which so many have killed and died.

I refuse my right to bear arms because I believe that Gandhi, Einstein, Sagan, Jesus, Buddha – and even Ayn Rand, whose words I’ll quote as a credibility-destroying concession to a young adulthood misspent re-reading Atlas Shrugged – agreed on one thing:

“Force and mind are opposites; morality ends where a gun begins.”

The wrinkling of your fingers when they are in water for a prolonged period of time is not because of them being ‘water logged’; it is actually an automatic nervous-system reaction, thought to be an evolutionary adaptation intended to give your hands better grip in wet conditions.

(Oooooh this is so good. I don’t think this is exactly what you were looking for but this is where my mind went. I hope you like it!)

Empathic abilities weren’t exactly common in the McCoy family, but they also weren’t a surprise when they do manifest. Every single case in his family usually manifested during puberty, and certainly no later than the age of twenty.

Definitely not thirty.

And yet here Leonard found himself, at the ripe age of thirty-one, wide awake and flooded with feelings of lust courtesy of one Jim Kirk’s wet dream on the other side of the room.

Keep reading

Splatoon World/Lore Headcanons

• All of the species in Inkopolis have their own native region where they are most concentrated (For example, The area around the Marianas Trench might be an independent nation called “Marianasia”, or perhaps in the waters around Greece we’d find the “United Mediterranean”, etc.)
• Inkopolis functions as a sort of global trade nexus; while we don’t see that side of it because our character is relatively young, it houses the equivalent of the NY stock exchange.
• The urchin homeland is kind of like modern day China in terms of mass-production output, except its largest export is clothing. However, due to the previously mentioned disputes, any product going to Inkopolis from the urchin homeland has incredibly high tariffs. Luckily, many of these products were imported before the tariff rise; however, this means that you can’t get any more of them without smuggling. This is Spyke’s business; he’s part of a smuggling ring which smuggles the shirts you order over the Urchin-Squid border, as the urchin homeland has the items in excess.
• Historically, there have been many disputes between the Inklings and Urchin peoples. While peace has been established, there’s still animosity between the races; hence why Spyke is hiding in alley.
• Anemone peoples’ “hair” is still immensely deadly to the touch. Luckily, many companies produce “anemone hair gel”, which acts like clownfish mucus, allowing Alanemone peoples to function in day-to-day life without putting the other races in danger. However, anemone “hair"sticks straight up as a result of this
• Clownfish, as a species, have a tendency to be confrontational. This is a vestigial evolutionary adaptation from when they would lure small fish to their native anemone so it could then be shocked and eaten by said anemone. While they are adjusting to nonviolent city life, it’s a slow process. This explains why Moe is always trying to pick a fight with Annie’s customers.


Due to a strange evolutionary adaptation to living at great oceanic depths, the flesh of the Greenland Shark contains a toxin that, when consumed, can make people drunk and hallucinatory. This rare and elusive creature, and its intoxicating meat, is the subject of author Morten Strøksnes’s new book, Shark Drunk: The Art of Catching a Large Shark from a Tiny Rubber Dinghy in a Big Ocean—a delightfully Quixotic fishing trip unlike any other committed to the page.

Fun fact:

There is a possibility that most cereals were toxic to us before we adapted to them (which makes all gluten related problems a lack if evolutionary adaptation on our part, much like with lactose).

And why did we even adapt to cereals? Because people were making beer with it.

That’s right. We can only eat cereals because some dude bros in Neolithic wanted to get wasted. Do what you want with this information.

anonymous asked:

honestly i didn't mean to kick the snek but it was on my foot and i was trying to shake it off and just general mortal fear took over. i couldn't remember the "red on yellow kill a fellow, red on black friend of Jack" saying, let alone have the sense of mind to look at the coloring. i just thought Kaa was trying to hypnotize me and eat me whole to assert his dominance and general superiority in evolutionary adaptations, thus i feel entirely justifiable in my anthropocentric reaction.

I think I can give you one (1) forgiveness if you promise to be kinder to sneks in the future.

anonymous asked:

Hi! I have a biology question for you. Its believed that many animals use bioluminescence to attract prey. I believe that works for insects, deep sea animals and stuff. But why then didn't those animals eventually evolve the instinct to avoid lights instead of going after them?

Yes, bioluminescence has widespread use amongst invertebrates, particularly marine invertebrates, as well as fishes and sharks etc., especially those that live in a deep sea habitat. 

Before I talk about bioluminescence specifically, I’ll just quickly run through some predator prey dynamics. The relationship between a predator and it’s prey can be seen as an arms race, i.e. the two are constantly evolving and adapting to try and have an edge over the other. For example, natural selection will favour a predator that can run faster and catch more prey than other members of the species, and be more likely to survive and produce more fast offspring, and thus the adaptation for faster running will evolve. On the flip side, there will also be a selective pressure for the prey species to become faster, and thus they evolve to outrun predators, and so you end up back to square one. This is also known as the Red Queen Hypothesis, after the Red Queen in Alice and Wonderland:

There is usually a balance met, an equilibrium between the effectiveness of both sides. Obviously animals can’t become infinitely fast - there were be physiological limitations, and various costs and for each adaptation - for example longer legs for running may make the animal more fragile and prone to breaking legs, or may make it lose body heat faster etc. Trade offs, and cost/benefit analyses, almost identical to those in economics, are fundamental to evolutionary biology. What adaptations are the most cost effective will change over a temporal scale, not only because of counter-adaptations in the other species, but also due to environmental and ecological factors which are constantly in flux. 

Usually the equilibrium tends to be in favour of the prey species, i.e. they have the edge, and in this example, more likely to outrun the predator. This due to something known as the life-dinner principle  - a predator will be running to catch it’s dinner, whereas the prey will be running for it’s life, i.e there is a much stronger selection pressure on the prey as for them it is a life or death situation, whereas the predator just loses a meal. This is why predators often pick off weak or injured prey - healthy adults will probably outrun them/be too dangerous/too much effort to catch. 

Additionally, one side of the race can “win” - if a predator becomes so good at catching prey it may wipe out the prey population, and will have to move on to different prey or die. Thus it’s usually in a predator’s interest not to be TOO good. This is also why predator population numbers are usually much smaller than their prey (predator populations rise -> more prey is eaten -> less food for everyone -> predators die of starvation and population falls -> prey population rises due to low numbers of predators -> cycle begins again, the classic example of this is the showshoe hare/lynx cycle ) 

Equally the prey could become so good at avoiding predation that, the predator again must move on to another prey source or die. We don’t really see these situations in nature because by definition, one side is extinct or is in a relationship with another species BUT we can see this happen with invasive species who outcompete native species and drive them to extinction. 

SO what your question seems to be asking is: why are bioluminescent predators that use light as a lure winning the arms race, why are prey species not evolving a counter adaptation, i.e. learning that bioluminescence is a trap? 

Well this luring behaviour is most common in the deep sea, and because of this, we have to take a lot of factors into account. First of all, bioluminescence in the deep sea is widely used and has many functions.  In can be used as camouflage, whereby light emitting organs line the belly of animals such as squid and fish, breaking up their silhouette from below.

It can be used as a defensive mechanism - many small crustaceans, plankton,  squid, and other invertebrates release clouds of bioluminescence ink to coat potential predators, making the predator itself more vulnerable to predation. 

Much like toxic animals on land like ladybirds and tree frogs use bright colours to advertise their toxic nature (aposematism), some animals like jellyfish use bioluminescence to signal their toxicity. Some animals, like dragonfish even use bioluminescent organs beneath their eyes as headlights to find prey.

A huge application for bioluminescence is communication, particularly for mate attraction. The deep sea is an unimaginably vast and empty place, so finding a mate in the darkness is very challenging. For example, ostracods (small shrimp like crustaceans) flash brightly to attract mates.

Since animals like ostracods are low in the food web, they are prey species for many deep sea animals, and thus many animals seek out flashing bioluminescence in order to find them. This is where luring animals, such as anglerfish come in, by mimicking bioluminescent prey species, they attract predators right to their mouth. Maybe now you can begin to see why simply avoiding lights to avoid predation wouldn’t be an option, it all comes back to costs and benefits

If an animal begins to avoid flashing lights, the benefit of not getting eaten may be outweighed by the cost of not finding food or not finding a mate (in evolutionary biology, not breeding is just as costly as dying). So, you can avoid predation, but will then either starve, or not pass on the genes for avoiding predation. Furthermore, the deep sea is so vast and spaced out that the probability of encountering a luring predator is negligible compared to  the probability of encountering your much more numerous prey species or mate. Thus, the proportion of the population lost to lure predation will be close to the rate of death from stochastic (random) events, and there will not be a strong selection pressure to develop an aversion for lures. 

Furthermore, luring predators like anglerfish tend to be opportunistic generalists - they will eat whatever they can get, and thus do not exert a strong predation pressure on any one species. If luring predators become more effective, and their population grows, then something similar to the lynx-hare cycle may occur. So all together, due to the deep sea environment and the ecology and population dynamics of the predator and prey species, arrive at equilibrium we have today - it’s not worth avoiding bioluminescence a) because it may have a direct cost to the prey, and b) the chances of being killed by traps is very low relative to the size of the prey population. 

We can look at terrestrial examples too. The larvae of fungus gnats (arachnocampa luminosa) in New Zealand live in caves and lay sticky bioluminescent threads from the ceiling to attract and trap flying insects. Flying insects such as moths use light (specifically starlight) for navigation, so adaptations for avoiding light are costly, as you may not be able to find food/mates as effectively. Furthermore, the populations of flying insects are so incredibly massive, that deaths from getting trapped in these rare caves is negligible, and thus there is not a strong selection pressure. 

Sorry if that was long, I hope it helps!

Abysmal sea creatures are so OUT THERE it makes me wonder if they look so cool because they don’t know what they look like and therefore have no sense of shame? LET ME REPHRASE THAT.

They live in the deep, right? And there’s barely any light, so they can’t REALLY see each other, they just rely on like, MINIMAL eyesight, and echolocation or smell? They have no sense of beauty, really. We have birds mating with the more colorful birds, and lionesses prefer darker mane, zebras and tigers striped to match their surroundings, but in the DEEP SEA the only thing they evolve to match their surroundings are either give light or go transparent. And they look like they evolve towards their eating habits, and mating is like “WELP, IT HAPPENS.”


The male angler fish latches onto the female angler fish and just FUSES IT’S HEAD AND BRAINS INTO THE FEMALE. It becomes PART OF HER. 

btw here’s the female

The male is literally just a SPERM-FILLED ZIT ON THIS THING. HOW INSANE???? ISS THAT???

And YEAH, I know LAND creatures have their share of creepy too, usually insects, just not to this extent? I’m bad at putting thoughts into words, but it’s like….

You see fish in the coral reef and they’re all colorful and beautiful, they blend in with the reef, they tell other fish if they’re a friend or foe, and they look like… FIIIIIIISH.


If anyone has reasons for why this is wrong or right, PLEASE INFORM ME

Fact: the common definition of demisexuals as “only feeling sexual attraction once a strong emotional bond is formed” is not entirely correct.  Demisexuals in fact only feel attraction once a telepathic/empathic bond has formed.

Unfortunately, demisexuals can only form this sort of bond with members of their own species, so demisexuals on Earth (surrounded by humans) may have difficulty finding suitable partners.  It is theorized that the lack of sexual attraction without a telepathic/empathic bond may be an evolutionary adaptation to avoid interspecies cross-breeding.