text: Yo, check it out, let me break it down for you
  In the world of cod, Gadus morhua L., yo, the calcium levels be true
  Expressed as a percentage of tissue dry weight, yo, listen up
  Before final maturation, the ovary calcium be 0.0042 plus or minus 0.0010 percent, what!
  When it comes to mature eggs, yo, it's 0.0133 plus or minus 0.0024 percent, ain't no joke
  
  Now let's talk about plaice, Pleuronectes platessa L., keep up, don't miss a beat
  0.0029 plus or minus 0.0006, that's the calcium level in the ovary, baby
  When it's all about those mature eggs, yo, it's 0.0097 plus or minus 0.0001, straight up!
  
  But hold up, hold up, let's compare it to the yolk of the domestic fowl
  Gallus domesticus L., yo, they got some high levels, for real
  0.14 percent of dry weight, that's the calcium they got goin' on, can you believe?
  One order of magnitude higher than these fish, yo, they on a different league
  
  Now let's talk iron, it's time to switch it up, pay attention now
  In cod, we talkin' (2.31 plus or minus 0.22) times 10 to the power of negative 3 percent, that's the ovary game
  When it comes to mature eggs, yo, it's (3.07 plus or minus 0.29) times 10 to the power of negative 3 percent, insane!
  
  Now for plaice, listen close, this is what we got
  (1.57 plus or minus 0.15) times 10 to the power of negative 3 percent, that's the ovary shot
  When it's all about them mature eggs, it's (2.74 plus or minus 0.94) times 10 to the power of negative 3 percent, yo, that's hot!
  
  But hold on, hold on, let's compare it to the yolk of the domestic fowl
  0.012-0.020 percent, that's the iron they got, oh wow!
  4-7 times higher than these fish, yo, it's a whole different game
  These marine teleosts ain't playin' the same, it's all about the sea water and the yolk's fame
  
  So there you have it, the differences laid out
  Between these fish and other oviparous vertebrates, no doubt
  Sea water availability, yolk phosphoprotein, and protein phosphorus, yo, they all play a part
  In these unique levels of calcium and iron, yo, it's science, it's an art.