C1 上級 1672 タグ追加 保存
動画の字幕をクリックしてすぐ単語の意味を調べられます!
単語帳読み込み中…
字幕の修正報告
Sperms aren't the mindless, flagellum-wielding, dolts that you thought they were.
Life is pretty tough for those little guys.
Hey dudes, Trace here with the lowdown on your sperms' struggles for DNews.
Sperm are the male gamete, the counterpart to the female's egg.
When a sperm reaches the inside of an egg, a zygote is created, which is the first step on the path to a fetus.
But to reach that goal, sperm have to overcome a lot of different problems, one being there are millions of other sperm in there.
And they're like, "Watch out, Dude!"
"I'm tryin' to get to the egg!"
For instance, we've evolved what science calls "sperm allocation."
As the point of sex is to get your sperm to the egg first and thus spread your genes, sperm allocation theory was one of nature's ways of getting the most bang for your buck.
If a male believes his female sexual partner has committed infidelity, or if he's simply spent a long while away from the partner, his sperm count will increase when they finally pair up!
The authors of a study published in "Current Directions in Psychological Science" believe this is why males get lustful feelings after being away from their partner for a while.
They want to make sure that they get back there and get some sperm in there as soon as possible to compete.
Once inside the woman, sperm continue their struggles.
This has to do with their creation: sperm are formed based on how the species fertilize and how much sexual competition is present.
It was assumed that the bigger the sperm, the faster they would be.
Bigger and stronger is better, right? Not so much.
A study published in the journal "Evolution" uses Bonobos as an example.
These apes share almost 99 percent of their DNA with humans and have a lot of sex with lots of different partners.
The competition has evolved sperm with bigger heads and a smaller tails.
The larger sperm were actually slower.
The researchers found only animals who fertilize outside of their bodies have large-sperm advantages.
The shorter head and longer tail of fish and squid sperm were super fast and thus got to the egg first.
Yeah bro!
Then there's the theory that there are two kinds of sperm: the goal scorers, and the ones who play defense.  
In humans, of the 250 million sperm cells released into the female reproductive system, 27 percent are defective, right off the bat.
The normally oval-shaped head is spherical or quite pointy in parts, the tails are malformed or whatever.
This theory of so-called "kamikaze sperm" also comes back to competition between mates.
The idea that these malformed sperm hang back to block other competing mates' sperm, thus ensuring the first male's domination of fertilization!
Since the hypothesis was proposed in the 80s, scientists have tried and failed to reproduce their findings, so while we're pretty sure this isn't real, it is still being tested.
Most scientists now believe the 27 percent defect rate occurs because of poor quality control in sperm creation, which is a little embarrassing.
Dudes, this is our big moment. We're half-assing out there!
110-percent, c'mon!
Of the millions of sperms released, remember you were the fastest.
So tell us your strategies down in the big empty white box below and subscribe!
Also, double check you're still following us on Twitter At-DNews. We made some changes.
You'll get behind-the-scenes pictures and some other cool stuff that sometimes doesn't make it into an episode. Thanks!
コツ:単語をクリックしてすぐ意味を調べられます!

読み込み中…

The Sperm Struggle is Real

1672 タグ追加 保存
lolitc 2015 年 3 月 8 日 に公開
お勧め動画
  1. 1. クリック一つで単語を検索

    右側のスプリクトの単語をクリックするだけで即座に意味が検索できます。

  2. 2. リピート機能

    クリックするだけで同じフレーズを何回もリピート可能!

  3. 3. ショートカット

    キーボードショートカットを使うことによって勉強の効率を上げることが出来ます。

  4. 4. 字幕の表示/非表示

    日・英のボタンをクリックすることで自由に字幕のオンオフを切り替えられます。

  5. 5. 動画をブログ等でシェア

    コードを貼り付けてVoiceTubeの動画再生プレーヤーをブログ等でシェアすることが出来ます!

  6. 6. 全画面再生

    左側の矢印をクリックすることで全画面で再生できるようになります。

  1. クイズ付き動画

    リスニングクイズに挑戦!

  1. クリックしてメモを表示

  1. UrbanDictionary 俚語字典整合查詢。一般字典查詢不到你滿意的解譯,不妨使用「俚語字典」,或許會讓你有滿意的答案喔