You have one choice. In front of you is a machine: if you put a coin in the machine, the other player gets three coins – and vice versa. You both can either choose to COOPERATE (put in coin), or CHEAT (don’t put in coin).

Exactly! Why let that moocher mooch off of you?

If you cooperate & they cheat, you lose a coin while they gain three. (score: -1 vs +3) However, if you both cheat, neither of you gain or lose anything. (score: 0 vs 0) Therefore: you should CHEAT.

Sure, seems like the right thing to do… OR IS IT?

Because if you both cooperate, you both give up a coin to gain three. (score: +2 vs +2) But if you cheat & they cooperate, you gain three coins at their cost of one. (score: +3 vs -1) Therefore: you “should” still CHEAT.

And that’s our dilemma. Trust is nice, but it can let others take advantage of you — or shoot you as you come unarmed out of a trench. Sometimes, distrust is rational! But now, what happens if we play this game…

Now, let’s play for real. You’ll be playing against 5 different opponents, each with their own game “strategy”. With each opponent, you’ll play anywhere between 3 to 7 rounds. (You won’t know in advance when the last round is) Can you trust them? Or rather… can they trust you?
ALWAYS CHEAT:the strong shall eat the weak
DETECTIVE: First: I analyze you. I start: Cooperate, Cheat, Cooperate, Cooperate. If you cheat back, I’ll act like Copycat. If you never cheat back, I’ll act like Always Cheat, to exploit you. Elementary, my dear Watson.

They called it: the “live and let live” system. Basically, you don’t shoot me, I don’t shoot you. And this worked, in a lot of places!


COPYCAT! (Apologies to your bet, Always Cheat.)

Copycat goes by many names. The Golden Rule, reciprocal altruism, tit for tat, or… live and let live

All that’s needed is that “unsuccessful” behaviors go away, and “successful” behaviors are imitated.

That’s right: the Always Cheats became a victim of their own success! They exploited the naive Always Cooperators, but once they ran out of them, they had to face the Copycats: who are nice, but not naive.

By simply copying the other player’s moves, Copycats can play nice with each other, while Always Cheats just cheat themselves! Not only that, but it also means Copycat can give Always Cheat a taste of their own medicine.

Copycat inherits the earth.

So, in the long run, you were right – Copycat wins! Always Cheat may have won in the short run, but its exploitativeness was its downfall. This reminds me of a quote:

“We are punished by our sins, not for them.”
~ Elbert Hubbard

So, it seems the math of game theory is telling us something: that Copycat’s philosophy, “Do unto others as you would have them do unto you”, may be not just a moral truth, but also a mathematical truth. However…

The Golden Rule

The golden rule is a basic moral directive that generally is phrased as “Do unto others as you would have them do unto you.” Many similar variations on this phrase are used. Most interpret this rule to mean people should treat others with the kindness, respect and consideration most individuals tend to expect for themselves. The golden rule is the basic foundation for many human-rights philosophies, and is associated with many world religions.

The Silver Rule

The silver rule is a variation and somewhat an inversion of the golden rule. The silver rule states “Do not do unto others as you would not have them do unto you.” The silver rule has its own deficiencies, as it only requires an individual not harm others, and does not ask that person to engage in positive behavior.


The golden rule is essential to many different world religions, and endorsed by and associated with various religious figures, including Jesus Christ, to whom the popular phrasing is attributed in the New Testament of the Bible. However, the golden rule predates Christ. According to Siegfried Morenz’s book “Egyptian Religion,” one of the earliest examples of the rule dates more than a thousand years prior to the existence of Jesus to an ancient-Egyptian concept called Maat.


Famous thinkers and critics such as writer George Bernard Shaw have publicly criticized the golden and silver rules for their oversimplified nature and somewhat problematic implications. Critics are dissatisfied with the second part of the golden and silver rules, which seemingly assume anyone can know exactly how others do and do not wish to be treated. As Shaw states in his work “Man and Superman: A Comedy and a Philosophy,” “Do not do unto others as you would that they would do unto you. Their tastes may not be the same.”

Maat or Ma’at (Egyptian mˤ3t)[1] refers to both the ancient Egyptian concepts of truth, balance, order, harmony, law, morality, and justice, and the personification of these concepts as a goddess regulating the stars, seasons, and the actions of both mortals and the deities, who set the order of the universe from chaos at the moment of creation. Her ideological counterpart was Isfet.

In 1985, when Americans were asked how many close friends they had, the most common answer was “three”. In 2004, the most common answer was “zero”. We now have fewer friends across class, racial, economic, and political lines, because we have fewer friends — period. And as you just discovered for yourself, the fewer “repeat interactions” there are, the more distrust will spread.
The same thing happens: with a lower “win-win” reward, Always Cheat takes over. Game theory has two powerful ideas about this:
“Zero-sum game”. This is the sadly common belief that a gain for “us” must come at a loss to “them”, and vice versa.

“Non-zero-sum game”. This is when people make the hard effort to create a win-win solution! (or at least, avoid a lose-lose) Without the non-zero-sum game, trust cannot evolve.


This strategy is better known in game theory as Tit For Tat. It was created by Anatol Rapoport in 1980, for Robert Axelrod’s game theory tournament. I chose not to use the name “Tit For Tat” because 1) it sounds mean, although it’s a nice & fair strategy, and 2) a lot of the public have already heard about Tit For Tat, so if I used that name, players might just place their bets on this character because they’ve already heard of “Tit For Tat”.

As cool as Copycat is, it has a huge, fatal weakness I haven’t mentioned yet. To understand the problem, let’s say two Copycats are playing against each other:
Mistakes, miscommunication, misinterpretations — accidents happen all the time in real life.
But if the other person doesn’t think it was an accident…
The other player, being a Copycat, had to retaliate…
…and you, being a Copycat as well, will also have to retaliate…
Thus, like the Hatfields and McCoys, these two Copycats will spiral into an endless cycle of vengeance… that started over a single mistake, long ago.
Tragic. But now, are there other types of players who can…  dealt with mistakes.

You were correct — Simpleton wins! This is because Simpleton is actually capable of exploiting Always Cooperate. They both start cooperating, but if Simpleton makes a mistake and cheats, since Always Cooperate never retaliates, it’ll keep cheating them.
You bet on Copycat. Again, go through the simulation…

Good guess, but someone else took the prize — Copykitten wins this time! That’s surprising that with an even meaner starting population, Copykitten, a more forgiving version of Copycat, was the most successful! (note: Copykitten is so forgiving it doesn’t even entirely wipe out Copycat. it shares room)

In this case, a bit of “miscommunication” (5% chance of mistake each round) could lead to more forgiveness. But is this true for all levels…

If there’s one big takeaway
from all of game theory, it’s this:

What the game is, defines what the players do.
Our problem today isn’t just that people are losing trust,
it’s that our environment acts against the evolution of trust.

That may seem cynical or naive — that we’re “merely” products of our environment — but as game theory reminds us, we are each others’ environment. In the short run, the game defines the players. But in the long run, it’s us players who define the game.

So, do what you can do, to create the conditions necessary to evolve trust. Build relationships. Find win-wins. Communicate clearly. Maybe then, we can stop firing at each other, get out of our own trenches, cross No Man’s Land to come together…

…to live and let live.
“A Christmas Truce between Opposing Trenches” Illustrated by AC Michael. Published in The Illustrated London News, January 9, 1915.

“We have fewer friends — period.”

Seriously, go read Robert Putnam’s 2000 book, Bowling Alone. Yeah it’s a bit outdated by now, 17 years later, but its core findings and lessons are still true as ever — probably even more so.


Also known as Pavlov, or Win-Stay-Lose-Shift.

The learning rule bases its decision only on the outcome of the previous play. Outcomes are divided into successes (wins) and failures (losses). If the play on the previous round resulted in a success, then the agent plays the same strategy on the next round. Alternatively, if the play resulted in a failure the agent switches to another action.


What Happened Before History? Human Origins


The world we live in feels normal, ordinary. It feels like this is just how humans exist and always existed. But, it’s not. Never before have we humans lived in a world as sophisticated and engineered to our needs as today. Giving us the luxury to forget about ourselves and not worry about survival. Food, shelter, security – all of this is, more or less, taken for granted. But we’re a special few; for more than 99.99% of human history, life was completely different.

And there’s no such thing as just one human history. Our story begins 6 million years ago, when the tribe of hominini split and our relationship with the apes ended. 2.8 million years ago, the genus of homo, the first humans, emerged. We like to think about ourselves as the only humans, but this is far from the truth.

When we, homo sapiens sapiens, came into existence 200,000 years ago, there were at least six other human species around. Cousins of comparable intelligence and ability, which must have been incredibly scary, kind of like living with aliens.

Some of them were very successful. Homo erectus, for example, survived for 2 million years. Ten times longer than modern humans have existed. The last of the other humans disappeared around 10,000 years ago.

We don’t know what caused them to die out. Modern humans have at least a few percent of neanderthal and other human DNA, so there was some mixing, but certainly not enough to be a merger between species.

So we don’t know if our cousins went away because they lost the battle over resources, or because of a series of minor genocides. Either way, only we remain. Back to the beginnings of humanity. 2.8 million years ago, early humans used tools, but did not make a lot of progress for nearly 2 million years.

Until they learned to control fire. Fire meant cooking, which made food more nutritious, which contributed to the development of our brain. It also produced light and warmth, which made days longer and winters less gruesome. On top of that, it not only scared predators away, it could also be used for hunting.

A torched wood or grassland provided small animals, nuts and tubers that were pre-roasted. From 300,000 years ago, most of the different human species lived in small hunter-gatherer societies. They had fire, wood and stone tools, planned for the future, buried their dead, and had cultures of their own. But most importantly, they spoke to each other. Probably in a kind of proto-language, less complex than ours.

If we had a time machine, how far would we be able to go back, steal a few babies and raise them today without anyone noticing that they’re a bit different? There is much debate. Anatomically, modern humans emerged 200,000 years ago, but probably 70,000 years is as far as we could travel back and still snatch a behaviourally modern human.

Before that, the babies would probably lack a few crucial gene mutations. Necessary to build a brain with modern language and abstract thinking abilities. At some point, around 50,000 years ago, there was an explosion in innovation. Tools and weapons became more sophisticated and culture became more complex, because at this point, humans had a multi-purpose brain, and a more advanced language to communicate information with each other effectively, and down to the last detail. This allowed much closer cooperation, and is what really makes us different from any other creature on Earth. Not our comparatively weak bodies and inferior senses, but the ability to cooperate flexibly in large groups, unlike, for example, rigid beehives or intimate, but tiny wolf packs.

As our brain evolved, we became able to do something, life had been unable to do up to this point. One – expand knowledge quickly. Two – preserve the knowledge gained over generations. Three – build on past knowledge, to gain even deeper insight.

This seems daft, but until then, information had to be passed on from generation to generation, mostly through genetics, which is not efficient. Still, for the next 40,000 years, human life remained more or less the same. There was little to build upon. Our ancestors were only one animal among many.

Building a skyscraper without knowing what a house is… is hard. But while it is easy to be arrogant in our attitude to our ancestors, this would be ignorant. Humans 50,000 years ago were survival specialists. They had a detailed mental map of their territory, their senses were fine-tuned to the environment, they knew and memorized a great amount of information about plants and animals.

They could make complicated tools that required years of careful training and very fine motor skills. Their bodies compared to our athletes today just because of their daily routines, and they lived a rich social life within their tribe. Survival required so many skills that the average brain volume of early modern humans might even have been bigger than it is today. As a group we know more today, but as individuals our ancestors were superior to us. But then around 12,000 years ago, in multiple locations, humans developed agriculture.

Everything changed very quickly. Before, survival as a hunter and forager required superb physical and mental abilities in all fields from everybody With the rise of the agricultural age, individuals could increasingly rely on the skills of others for survival. This meant that some of them could specialize. Maybe they worked on better tools, maybe they took time to breed more resistant crops or better livestock, Maybe they started inventing things. As farming got more and more efficient, what we call civilization began. Agriculture gave us a reliable and predictable food source, which allowed humans to hoard food on a large scale for the first time, which is much easier to do with grains than meat, the food stock required protection, which led to communities living together in tighter spaces first, early defense structures were built, the need for organization grew.

The more organized we got, the faster things became efficient. Villages became cities, cities became kingdoms, kingdoms became empires. Connections between humans exploded which led to opportunities to exchange knowledge. Progress became exponential. About 500 years ago the Scientific Revolution began Mathematics, Physics, Astronomy, Biology, and Chemistry transformed everything we thought we knew.

The Industrial Revolution followed soon after laying the foundation for the modern world As our overall efficiency grew exponentially, more people could spend their lifetime contributing to the progress of humanity revolutions kept happening. The invention of the computer, its evolution into a medium we all use on a daily basis, and the rise of the Internet shaped our world It’s hard to grasp how fast all of that happened It’s been about 125,000 generations since the emergence of the first human species.

About 7,500 generations since the physiologically modern humans saw the light of day 500 generations ago, what we call civilization began 20 generations ago, we learned how to do science. And the Internet became available to most people only one generation ago Today we live in the most prosperous age humanity has ever experienced. We have transformed this planet, from the composition of its atmosphere to large-scale changes in its landscape and also in terms of the other animals in existence.

We light up the night with artificial stars and put people in a metal box in the sky. Some have even walked on our moon. We put robots on other planets. We’ve looked deep into the past of the universe with mechanical eyes. Our knowledge and our way of acquiring and storing more of it has exploded.

The average high school student today knows more about the universe than a scholar a few centuries ago. Humans dominate this planet, even if our rule is very fragile. We are still not that different from our ancestors 70,000 years ago. But your lifestyle has existed for less than 0.001% of human history. From here on, there’s no saying what the future holds for us. We’re building a skyscraper, but we’re not sure if it’s standing on a solid foundation or if we’re building it on quicksand.

Let’s leave it with that for now. The next time you miss your train, your burger is not hot enough, or someone cuts in line. Remember how special this made-up human world is…

Maybe it’s not worth being upset about all those little things.

Hukum Termodinamika II dan Evolusi : Part 1


[Penjelasan Istilah Sistem Dalam Termodinamika]

1. Open System     :  Bahwa adanya pertukaran materi dan energi
2. Closed System   : Bahwa adanya pertukaran energi tetapi tidak dengan materi
3. Isolated System  : Bahwa tidak adanya pertukaran energi ataupun materi


Entropi ialah tingkat penyebaran energi di dalam suatu sistem. Sering kali dikasih definisi sebagai derajat ‘kekacauan dalam suatu sistem’.
Sebenarnya entropi itu sedikit lebih absrak dan hukum kedua termodinamika menyatakan bahwa alam semesta akan meningkat keseragamanya, dalam hal apa? Dalam hal panas, atau transfer ‘heat energy ‘ dimana panas dalam alam semesta akan menyebar hingga keseluruhan bagian di alam semesta memiliki termprature dan tingkatan energi yang sama (dalam prosedur pertukaran panas, panas selalu ditransferkan dari objek/wilayah yang memiliki temprature yang tinggi ke temprature yang lebih rendah, hingga keseimbangan termprature dari kedua objek/wilayah seimbang atau mencapai keseimbangan.

Dengan kata lain, semuanya yang dalam sistem terisolasi/isolated system cenderung menjadi seimbang. Ketika alam semesta telah mencapai titik ‘equilibriumnya’ maka hilanglah semua daya dukung alam semesta untuk mensupport kehidupan dimanapun, atau tidak ada tempat yang ramah bagi kehidupan. : http://bigthink.com/dr-kakus-universe/the-big-freezehttp://www.spaceanswers.com/deep-space/what-is-heat-death/
Atau simpelnya : seiring dengan waktu, sebuah ruang akan menjadi ‘disorder’, menjadi lebih ‘kacau’ (bahwa materi akan terdistribusikan secara rata diseluruh tempat, bukan sebaliknya hanya terkonsentrasi di beberapa tempat saja).

Jadi gini analoginya, semua energi, entah itu dari tubuh kita, atau dari mesin akan dikonversi menjadi energi panas (menghasilkan panas – bekerja menghasilkan panas), dan panas itu akan menyebar secara merata diseluruh alam semesta hingga alam semesta mencapai titik ‘equilibriumnya’. Ketika alam semesta mencapai titik keseimbanganya maka tidak ada aktivitas/gerakan lagi di alam semesta, karena aktivitas ialah dimana energi seharusnya terkonsentrasikan dalam suatu tempat/tidak ada lagi energi yang dapat terkonversi.

Apakah evolusi melanggar hukum termodinamika kedua?

Seperti yang telah kita ketahui bahwa hukum alam tidak bisa dilanggar, salah satunya hukum termodinamika kedua yang menyatakan bahwa kekacuan selalu meningkat, sayangnya beberapa orang berfikir bahwa ini merupakan masalah bagi evolusi yang memfalsifikasi datangnya asal muasal kehidupan secara natural. Tapi pada dasarnya kehidupan mematuhi ‘scientific law’.

Apa sih hukum kedua dari thermodynamics? Itu mengatakan bahwa dalam sebuah ‘isolated system’ bahwa entropy akan cenderung meningkat. Tapi kerasionist suka memutar balikan arti dari hukum termodinamika ini dalam agenda mempromosikan agama dan propaganda mereka, sangat benar-benar kacau, mereka tidak perduli apa itu science sebenarnya tapi mereka hanya memandang science ialah sesuatu bidang yang harusnya mendukung posisi iman mereka, ya bisa dibilang ‘cherry-picking’.

Mereka selalu menyamakan kata ‘entropy’ dengan ‘disorder’, dan mereka bilang ‘disorder’ selalu meningkat seiring waktu, oleh karena itu maka ini membantah evolusi yang menyiratkan bertambahnya kompleksitas/susunan dari organisme entah bagaimana melanggar hukum termodinamika kedua yang menjadikan ‘more order then disorder’. Ini ialah ironi, bagaimana mereka menggunakan science untuk membantah science. Hilarious! Creationists are so funny!

Ada sebuah ide yang selalu digunakan banyak orang yang anti evolusi untuk membuktikan membantah) ‘biological evolution’ itu tidak mungkin. Yaitu ide yang mencoba mempertentangkan hukum termodinamika II dengan evolusi. Bagaimana pun ide tersebut berasal dari ‘a flawed understanding’ mengenai hukum termodinamika II, faktanya teori evolusi tidaklah bertentangan dengan hukum-hukum fisika yang ada (read: Hukum termodinamika II).
Bagaimanapun juga hukum termodinamika II tidak mencegah adanya keteraturan ‘order’ di suatu bagian wilayah dari sistem yang terutup selama ada suatu bagian/wilayah lain dari sistem tersebut yang ‘disordered’. Disorder > order = sesuai dengan hukum termodinamika II bahwa entropi selalu meningkat seiring waktu.

Contohnya ada banyak dari kejadian sehari-hari kita yang membuktikan bahwa mungkin kok untuk membuat ‘order’ keteraturan, misalnya bahwa ada orang yang menebang beberapa pohon, membentuk menjadi tiang kayu, dan membangun rumah dari bahan baku pohon-pohon tersebut. Tetapi kan dalam proses pengkerjaanya seorang tersebut telah mengeluarkan panas, dari tubuhnya, mesin, aktivitas kegiatanya yang mana panas akan meningkat seiring meningkatnya entropi dari keseluruhan alam semesta.

Bayangkan ada 2 batttery yang menyimpang energi, itu tidak harus battery tapi bisa juga medium apapun yang dapat  menyimpan energi, hukum kedua termodinamika menyatakan kapanpun elu melakukan transfer energi dari suatu sistem ke sistem lainya, elu tidak akan mendapatkan 100 % efficiency, ketika elu mencharge battery A dari battery B, elu tidak mendapatkan full efficiency. Nah lalu kemana sisa energynya pergi, itu lepas menuju kesekeliling, ini juga menjadi alasan kenapa ketika elu mencharge HP, itu akan menjadi panas karena energi terlepas (tidak efficient).

Ketika energi lepas-terbuang-hilang itu akan menjadi sulit untuk digunakan, dan ketika tidak ada energi yang dapat dikonvert menjadi susuatu energi yang dapat digunakan maka itu akan menjadikan ‘state of equilibrium’. Jadi pada ‘isolated system’ dimana elu punya energi yang sedang ditransferkan dari sekeliling elu, elu akan tetap kehilangan energi sebagai panas dan ini akan menjadikan entropi meningkat. Dalam suatu sistem ketika energi dapat disimpan/tidak digunakan maka entropy akan rendah, sebaliknya apabila energi yang disimpan sedikit maka banyak yang dilepaskan menjadi ‘useless heat’ yang menyebabkan entropi meningkat. Dalam sistem terisolasi dimana tidak adanya intervensi dari sistem lainya akan menyebabkan entropi meningkat.

Atau contoh lain, misalnya coba bayangkan ketka cucah berubah dan di luar menjadi dingin, udara dingin memiliki entropi yang sedikit daripada udara hangat pada umumnya, dan itu terhitung sebagai ‘ordered’ karena molekul-molekul tidaklah bergesekan satu sama lain atau tidak bergerak cepat ke sekitar dan cenderung tenang – terkumpul di beberapa tempat. Itu menyiratkan bahwa entropi di tempat kita local place) cenderung ‘more ordered’ – turun, tetapi selama ditemani peningkatan entropi ditempat lain, maka hukum termodinamika II tidaklah terlanggar. Dengan kata lain untuk hal tertentu, entropi memang bisa menurun (semakin teratur). Tapi ini bukan tanpa pengorbanan. Untuk menurunkan entropi diperlukan energy. Dan bumi yang memiliki kehidupan yang memiliki entropi relatif rendah ini berkat energi dari matahari.

Tapi kalo dilihat lagi dari grand schemenya seluruh jagat raya, entropi memang akan terus meningkat. Keteraturan akan berubah menjadi ketidak-teraturan.

Itu ialah gambaran umum bahwa alam memungkinkan ‘generating order out of disorder’ di area lokal – tempat tertentu tanpa melanggar hukum termodinamika II, dan itulah hal yang sama yang terjadi pada teori evolusi – abiogenesis.

Disisi lain ada orang yang mengatakan bahwa kita yang berasal dari bakteri telah melanggar hukum termodinamika II : “Teori evolusi menyatakan bahwa atom-atom dan molekul-molekul tidak hidup yang tak teratur dan tersebar, sejalan dengan waktu menyatu dengan spontan dalam urutan dan rencana tertentu membentuk molekul-molekul kompleks seperti protein, DNA dan RNA. Molekul-molekul ini lambat laun kemudian menghasilkan jutaan spesies makhluk hidup, bahkan dengan struktur yang lebih kompleks lagi. Menurut teori evolusi, pada kondisi normal, proses yang menghasilkan struktur yang lebih terencana, lebih teratur, lebih kompleks dan lebih terorganisir ini terbentuk dengan sendirinya pada tiap tahapnya dalam kondisi alamiah. Proses yang disebut alami ini jelas bertentangan dengan Hukum Termodinamika II – Entropi.

TAPI ‘complexity in living organisme’ disatu sisi menaikan ‘amount of order’. Contohnya amino acids akan tersusun/berubah menjadi polupeptide yang mana jauh lebih besar serta lebih kompleks secara protein. TAPI disisi lainya ‘living organisme’ juga menaikan ‘disorder’, misal organisme kompleks mengambil suatu energi dari sekitarnya seperti menyerap sinar matahari yang nyatanya menguras hidrogen dan helium matahari.

Bagaimana dengan bumi, mari kita ‘flashback’ mengenai argument kerasionist yang menyatakan bahwa hewan terlah berevolusi menjadi struktur yang lebih kompleks, tapi ini melawan hukum kedua termodinamika karena terkesan lebih menjadi ‘ordered’ which supposed to be more ‘disordered’, nah disini kita memakai analogi bahwa ‘living organism’ di bumi sebenarnya ialah medium penyimpanan energi, ‘living organism’ menyimpan energi dari matahari. Itu akan membuat suatu pelanggaran terhadap hukum termodinamika kedua APABILA energi yang makhluk hidup dapat dari matahari entah bagaimana lebih besar atau menjadi seimbang dari energi yang dikeluarkan matahari terhadap kita (high efficiency). Tapi kan engga, lebih banyak sinar matahari yang terubuang sia-sia yang kita tidak dapat manfaatkan atau contoh lainya tumbuhan menyerap sinar matahari, rusa memakan tumbuhan, ini seperti analogi transfer energi pada battery, kita tidak bisa mendapatkan ‘high efficiency’, begitu juga yang terjadi pada evolusi yang mengarah ke kompleksitas, itu tidak akan melanggar hukum termodinamika kedua selama ‘ADANYA ENERGI YANG TERBUANG’.

– Slave

Sambungan : http://line.me/R/home/public/post?id=hao1445q&postId=1147736251809030862



Jika ada yang bisa disebut sebagai manusia pertama, maka itu adalah kelompok spesies Homo sapiens pertama.

Pertama, tentang spesies. Spesies adalah satu pengelompokan organisme yang anggota-anggotanya bisa saling kawin dan menghasilkan keturunan fertil. Kuda dan keledai adalah spesies yang bebeda karena, sekalipun jika kuda kawin dengan keledai menghasilkan keturunan berupa bagal, keturunannya tidak fertil, alias steril. Bagal tidak bisa berketurunan baik kalau kawin dengan kuda, keledai, atau sesama bagal.

Kemudian, tentang spesiasi atau proses terjadinya spesies baru yang terbedakan dari spesies nenek moyangnya. Proses berubahnya mahluk hidup terjadi karena adanya mutasi gen yang terwariskan. Mutasi atau perubahan ini biasanya tidak besar dan drastis atau tiba-tiba dan sekaligus, tetapi kecil-kecil dan berangsur-angsur. Setelah sekian lama, dalam jutaan tahun, sekelompok organisme yang membawa akumulasi perubahan kecil-kecil itu telah menghasilkan organisme yang signifikan perbedaannya. Sedemikian berbedanya sehingga tidak bisa lagi menghasilkan keturunan fertil dengan spesies ‘asal-usul’ atau spesies ‘baru’ lainnya yang berevolusi bersama dari nenek-moyang yang sama tetapi berevolusi menuju ke arah yang lain.

Kalau agak bingung, spesiasi itu misalnya, ini contoh yang agak kasar: dinosaurus, sebagian keturunannya perlahan berubah menjadi biawak, sementara sebagian lagi berevolusi menjadi kutilang. Karena kutilang sudah sedemikian berubahnya, ia tidak bisa lagi kawin dengan dinosaurus dan menghasilkan keturunan yang fertil. Begitu pula kutilang adalah spesies yang berbeda dengan biawak, karena walaupun sama-sama keturunan dinosaurus, mereka berdua tidak bisa kawin dan menghasilkan keturunan yang fertil.

Kembali ke pertanyaan, siapakah kelompok spesies Homo sapiens pertama?

Kelompok Homo sapiens pertama adalah keturunan Nakalipithecus yang hidup 16 juta tahun yang lalu. Dari satu spesies tersebut, sebagian berevolusi menjadi gorila, sebagian lagi menjadi simpanse, bonobo, dan sebagian menurunkan genus Homo (dengan beberapa spesies). Spesies tertua dari genus Homo, yang sejauh ini sudah dipelajari fosilnya adalah Homo habilis yang hidup kurang lebih 2,5 juta tahun yang lalu. Genus homo ini juga terus berevolusi dan mengalami proses spesiasi menjadi spesies-spesies Homo lainnya. Dalam genus Homo tersebut, spesies Homo erectus kemudian menurunkan Homo sapiens, kira-kira 400.000 tahun yang lalu.

Jadi, (kelompok) manusia pertama adalah kelompok Homo sapiens pertama, yang hidup 400.000 tahun yang lalu, dan yang telah mengalami spesiasi dari ‘induk’ dan ‘sepupu’nya sehingga tidak bisa lagi saling kawin mawin dengan ‘induk’ dan ‘sepupu’nya dan menghasilkan keturunan fertil.

Dari sudut pandang teori evolusi, pertanyaan siapakah manusia pertama sebetulnya adalah pertanyaan: bagaimana proses munculnya spesies Homo sapiens.

there was no first man and first women in evolution

Jika berminat, sila kunjungi:



kenapa sperma bisa menemukan ovum secara akurat dan tidak tersesat? (yang jelas bukan karena adanya tuhan yang menyuruhnya)


Sperma bisa ketemu sel telur, mayoritasnya karena proses kimiawi, semuanya merupakan fenomena alami, pada sperma ada binding protein yang namanya izumol, dan pada permukaan sel telur ada protein reseptor yang disebut folr4, sekarang diberi nama Juno
sperma tahu ke mana arahnya karena mereka bisa mendeteksi dimana kandungan sinyal kimiawi yang dikeluarkan sama ovumnya

Namanya kemotaksis/chemotaxis sperma, proses dimana sel sperma mengikuti stimulus kimiawi yang dikeluarkan oleh sel telur, sampai sperma menemukan sel telur tersebut, sisanya diatur oleh protein pengikat izumol dan protein reseptor juno, dalam perkembangannya, kemotaksis ini digunakan sebagai mekanisme kritis dalam perkembangan, termasuk pergerakan sperma menuju ovum, dan migrasi neuron atau sel-sel darah putih tertentu
” .. sperm cells (spermatozoa) follow a concentration gradient of a chemoattractant secreted from the oocyte and thereby reach the oocyte.”

Nah, oosit ini sudah mengsekresikan bahan kimia, semakin dekat dengan oosit, semakin ‘kuat’ sinyal dari bahan kimia ini. Sperma mengikuti bahan kimia ini. Analoginya seperti anjing pelacak lah, dia mengendus bau, ketika baunya semakin kuat maka apa yang dia cari sudah semakin dekat. In short karena adanya chemoattractant ini sperma bisa mencari ovum.

chemotaxis: jadi si sperma mengikuti molekul yang dikeluarkan oleh ovum :
ada 2 jenis chemo-attractant (bahan kimia yang membuat sperma tertarik: satunya dari oocyte (tapi masih belum diketahui) dan dari progesterone) thermotaxis: adanya perbedaan suhu antara uterus dan oviduct secara tidak langsun mengarahkan sperma ke oviduct sehingga semakin dekat dengan ovumnya

Karena proses evolusi dan seleksi alam, kemotaksis bukan cuma milik sperma dan ovum, tapi merupakan pergerakan setiap organisme baik bersel satu ataupun multiseluler, dengan respon terhadap rangsangan kimiawi
sel somatik, bakteri, dan organisme sejenis melakukan pergerakan mereka tergantung pada bahan kimia tertentu di lingkungan, ini sudah dikembangkan sejak jaman organisme yang ada hanya protosel saja, digunakan untuk menemukan makanan, atau lari dari racun, ini disebut kemotaksis positif, dan kemotaksis negative

mekanisme ini sudah dikembangkan selama milyaran tahun, dan diadopsi oleh seluruh mahkluk hidup, termasuk tumbuhan, dan hewan, dan tentunya mamalia juga