1 00:00:00,560 --> 00:00:09,320 Greetings! This is a video to teach you how to calculate and create a calendar 2 00:00:09,320 --> 00:00:16,100 that represents the Earth's past as if it had lasted only one year. Then, as you 3 00:00:16,100 --> 00:00:25,559 know, the Earth formed 4600 million years ago and it is divided into eons and we 4 00:00:25,559 --> 00:00:33,420 studied how the last aeon, the Phanerozoic aeon, is divided into three eras. The first aeon, the 5 00:00:33,420 --> 00:00:41,380 Hadean aeon, had a lot of meteoritic impacts. It started 4,600 million years ago. It finished 6 00:00:41,380 --> 00:00:47,119 approximately 4,000 million years ago. It was followed by the Archean aeon, in which life 7 00:00:47,119 --> 00:00:54,460 appeared and the tectonic plates were already moving. Then we have the Proterozoic aeon at this 8 00:00:54,460 --> 00:01:03,700 beginning, with descent, and then in the Proterozoic Eon, well, we know that there were no animals 9 00:01:03,700 --> 00:01:11,299 like now, but life was evolving, then finally we have the Phanerozoic Eon, which begins 10 00:01:11,299 --> 00:01:13,219 with the Cambrian Explosion, okay? 11 00:01:13,280 --> 00:01:19,959 The Cambrian Explosion is the apparently sudden appearance of the main types of animals that 12 00:01:19,959 --> 00:01:20,620 exist now. 13 00:01:20,620 --> 00:01:28,620 So the Cambrian is the beginning of the Phanerozoic Eon, and it begins with the Paleozoic Era. 14 00:01:28,620 --> 00:01:36,620 The era in which there were trilobites, there were different kinds of animals, first in the oceans, then in the continents. 15 00:01:36,620 --> 00:01:41,620 Fish evolved from fish amphibians and then reptiles. 16 00:01:41,620 --> 00:01:53,620 Then 250 million years ago the Paleozoic era finished with the Permian to Triassic mass extinction 17 00:01:53,620 --> 00:01:58,620 and that was the beginning of the Mesozoic era, which was the era of the dinosaurs 18 00:01:58,620 --> 00:02:03,620 and the era also in which mammals and birds evolved. 19 00:02:03,620 --> 00:02:13,620 It started 250 million years ago and it finished 66 million years ago with the extinction of the last non-avian dinosaurs, 20 00:02:13,620 --> 00:02:21,620 which was the beginning of the Cenozoic era, which is the era in which we live now, and was the era of the expansion of mammals. 21 00:02:21,620 --> 00:02:30,620 Since the Cambrian is the beginning of the Phanerozoic eon, approximately 545 million years ago, 22 00:02:30,620 --> 00:02:38,460 Then all the time before that, which is most of the existence of the Earth, is called the Precambrian. 23 00:02:43,379 --> 00:02:51,020 Well, then all this history of the Earth took 4600 million years. 24 00:02:51,479 --> 00:02:57,199 But now we want to calculate what if it had lasted only one year? 25 00:02:57,199 --> 00:03:02,219 If it had lasted one year, then how much of that year would have been the Hadean Aeon? 26 00:03:02,219 --> 00:03:06,219 how much would have been the Archaean Aeon, etc. 27 00:03:06,219 --> 00:03:10,219 Ok, so what we want to do is something like this image here. 28 00:03:10,219 --> 00:03:14,219 This is an image in which we have one year, so January, 29 00:03:14,219 --> 00:03:18,219 February, March, the different days in one year. So 30 00:03:18,219 --> 00:03:22,219 January has 31 days, then February usually has 28, March 31 00:03:22,219 --> 00:03:26,219 again 31, April 30. So we want, with colors, 32 00:03:26,219 --> 00:03:30,219 we want to indicate how much of this 33 00:03:30,219 --> 00:03:38,219 how many days will have been the Hadean eon, then the Archean eon, the Proterozoic eon, etc. 34 00:03:38,219 --> 00:03:41,219 And we want to calculate that with Excel. 35 00:03:41,219 --> 00:03:53,219 So that's why you have in my website and in Teams this Excel file in which we are going to perform the calculations 36 00:03:53,219 --> 00:03:59,219 and also you have another sheet in Excel in which you have this calendar, 37 00:03:59,219 --> 00:04:05,219 this 2020 calendar, in which we will color the different days 38 00:04:05,219 --> 00:04:10,219 depending on the eons they represent. 39 00:04:10,219 --> 00:04:16,220 So the days that represent the Hadean eon will be in red, 40 00:04:16,220 --> 00:04:19,220 then the ones of the Archean eon will be light green, 41 00:04:19,220 --> 00:04:22,220 the Proterozoic eon will be yellow, etc. 42 00:04:22,220 --> 00:04:24,220 So how do we perform these calculations? 43 00:04:24,220 --> 00:04:27,220 Well, the first thing we have to do is we have to tell Excel 44 00:04:27,220 --> 00:04:31,220 cell to calculate the length of each of these eons. 45 00:04:31,220 --> 00:04:35,220 For instance, for the Hadean eon what we have to do is we click 46 00:04:35,220 --> 00:04:39,220 on the cell, then we type the equal sign and 47 00:04:39,220 --> 00:04:43,220 we indicate that we want to subtract from this cell 48 00:04:43,220 --> 00:04:47,220 we subtract this other cell. 49 00:04:47,220 --> 00:04:51,220 So this cell minus this cell 50 00:04:51,220 --> 00:04:55,220 we press enter is 600 million years. So now we see that 51 00:04:55,220 --> 00:05:00,860 the Hadean eon was 600 million years, which of course is very easy to calculate with this. 52 00:05:00,860 --> 00:05:05,560 For the Archean eon we will do the same, we will subtract 4000 million years ago, which 53 00:05:05,560 --> 00:05:10,079 is the beginning, minus 2500 million years. 54 00:05:10,079 --> 00:05:18,300 Also the easiest way to do that is we just copy what we wrote for the Hadean eon and 55 00:05:18,300 --> 00:05:23,759 then we paste that formula, only the formula, here. 56 00:05:23,759 --> 00:05:32,060 So this way what Excel has done is it has copied the formula on this cell, on this other 57 00:05:32,060 --> 00:05:35,259 cell, but it has changed the numbers. 58 00:05:35,259 --> 00:05:40,879 So instead of using the numbers of the red row it has used the ones of the light row. 59 00:05:40,879 --> 00:05:45,800 And I can do the same here and remember we are going to paste only the formula because 60 00:05:45,800 --> 00:05:52,300 if we paste all of it we will also paste the format color which we don't want to do. 61 00:05:52,300 --> 00:06:00,360 Then I paste it also here, and I have made a little mistake here. 62 00:06:00,360 --> 00:06:04,740 Let me correct it. 63 00:06:04,740 --> 00:06:14,060 I don't know why there was a little mistake here, but I am going again to copy the calculation 64 00:06:14,060 --> 00:06:20,459 I told it to perform, then I paste only the formula, and then here it is. 65 00:06:20,459 --> 00:06:26,480 And I am going to do the same in the other cells. 66 00:06:26,480 --> 00:06:33,259 So I paste only the formulas and here I paste only the formulas. 67 00:06:33,259 --> 00:06:39,040 So then this way we have the length of every eon and every era. 68 00:06:39,040 --> 00:06:45,000 Now we want to know what percentage it is inside the Earth's existence for the Hadean. 69 00:06:45,000 --> 00:06:50,620 Then I click here on this cell and then I type the equal sign. 70 00:06:50,620 --> 00:06:54,060 Then what we want to do is, we want a percentage. 71 00:06:54,060 --> 00:07:01,860 So I will start by multiplying 100 times this length here, this cell. 72 00:07:01,860 --> 00:07:07,079 And the result has to be divided by the total length of the Earth's existence, which was 73 00:07:07,079 --> 00:07:09,420 4600 million years. 74 00:07:09,420 --> 00:07:13,779 I may type that number, but instead I will choose this cell. 75 00:07:13,779 --> 00:07:22,839 When we press enter, then we see that approximately 13% of the Earth's existence was the Hadean 76 00:07:22,839 --> 00:07:23,839 Eon. 77 00:07:23,839 --> 00:07:27,540 Now, we want to do the same here, but there is a little problem. 78 00:07:27,540 --> 00:07:35,420 The little problem is that here we also want to multiply times 100 the length of the Eon, 79 00:07:35,420 --> 00:07:43,160 but we don't want to divide it by the number here, the 4000 million, but we want to divide 80 00:07:43,160 --> 00:07:47,160 by the total existence of the Earth which is 4600. 81 00:07:47,160 --> 00:07:54,160 So then, to do that, what I have to do is first I copy this formula, 82 00:07:54,160 --> 00:08:01,160 but in this formula, as you can see, I have indicated the C4 cell 83 00:08:01,160 --> 00:08:08,160 and it is not locked. It means when I paste the formula for the Archeaneum 84 00:08:08,160 --> 00:08:10,160 The computer has no idea what we are doing. 85 00:08:10,160 --> 00:08:13,160 It will simply use the equivalent cell. 86 00:08:13,160 --> 00:08:14,160 I don't want to do that. 87 00:08:14,160 --> 00:08:18,160 I want to use the 4600 for all of them. 88 00:08:18,160 --> 00:08:23,160 So what I do is I type the dollar symbol in front of the C 89 00:08:23,160 --> 00:08:28,160 and I type the dollar symbol in front of the 4. 90 00:08:28,160 --> 00:08:32,159 If I do that, then the result here doesn't change. 91 00:08:32,159 --> 00:08:36,159 But what I'm telling Excel is that for every cell I type here, 92 00:08:36,159 --> 00:08:42,159 The division I want it to be by the 4600, 93 00:08:42,159 --> 00:08:45,159 by the content of this cell here. 94 00:08:45,159 --> 00:08:47,159 So now that I have indicated that, 95 00:08:47,159 --> 00:08:51,159 then now I can copy and I can paste only the formula 96 00:08:51,159 --> 00:08:53,159 to keep the format. 97 00:08:53,159 --> 00:08:55,159 Then I will also do it here, 98 00:08:55,159 --> 00:08:59,159 and let us see, I will also do it here, 99 00:08:59,159 --> 00:09:02,159 and then I will also do it here, 100 00:09:02,159 --> 00:09:05,159 and I will also do it here. 101 00:09:05,159 --> 00:09:10,039 So this way we see the percentage inside of all of Earth's history for each of these 102 00:09:10,620 --> 00:09:17,259 eons and eons. Okay, and then now once we have the percentage now we can calculate the equivalence in days 103 00:09:17,820 --> 00:09:22,159 for each of these percentages and what I do is I click here then I 104 00:09:22,860 --> 00:09:27,919 type equal then I select this cell and I multiply it 105 00:09:28,740 --> 00:09:30,460 times 106 00:09:30,460 --> 00:09:38,779 And since what I have in the percentage is a percentage, and it has been multiplied times 107 00:09:38,779 --> 00:09:44,799 100, then I am going to divide it by 100 so that I get the right number. 108 00:09:44,799 --> 00:09:51,559 Which means the Hedian Eon will be the equivalent of approximately 48 days in a year. 109 00:09:51,559 --> 00:09:58,700 Now that I have typed that formula, then I am going to paste the formula in the other 110 00:09:58,700 --> 00:10:08,360 cells and this way I am calculating how many days each of the eons and eras is. 111 00:10:08,360 --> 00:10:16,580 Okay, and then once I have done this, once I have indicated that, now in the 2020 112 00:10:16,580 --> 00:10:25,220 calendar I can start coloring. Okay, so as you see approximately 48 days in a year 113 00:10:25,220 --> 00:10:32,419 will be the Hadean Aeon. The Hadean Aeon has this color, okay? So I am going to 114 00:10:32,419 --> 00:10:42,019 copy the format and then in the 2020 calendar these days will have that red 115 00:10:42,019 --> 00:10:49,279 color. I also paste, well copy the format, I select also these days in January, then 116 00:10:49,279 --> 00:10:52,620 Then again I copy the format. 117 00:10:52,620 --> 00:11:00,179 This way the 31 days of January are labelled red as the Hadean Eon. 118 00:11:00,179 --> 00:11:05,120 But the Hadean Eon we calculated was 48 days. 119 00:11:05,120 --> 00:11:09,200 So this means the 31 days of January are not enough. 120 00:11:09,200 --> 00:11:13,320 We need 17 more days which will be from January. 121 00:11:13,320 --> 00:11:17,000 So I have to copy the format. 122 00:11:17,000 --> 00:11:24,000 Then I select this number of days, I select also this number of days, and, well, no, I 123 00:11:24,000 --> 00:11:30,600 did it wrong here, yes, because I have to select only one cell, only one cell here, 124 00:11:30,600 --> 00:11:34,440 and then I select the format, here it is. 125 00:11:34,440 --> 00:11:41,759 Ok, so now we have the 48 days that represent the Hadean in the same color as the Hadean. 126 00:11:41,759 --> 00:11:59,019 Ok, and now I will have to do the same for the Archea Neon, 119 days will be the light color, I copy the format and then I start selecting these days in February to do the same. 127 00:11:59,019 --> 00:12:12,019 And I will have to select more days, like this, in March, and so on, until I reach the 119 days for the Archean Eon. 128 00:12:12,019 --> 00:12:19,019 Then I will select the yellow color for the Proterozoic Eon, which will be 155 days, and so on. 129 00:12:19,019 --> 00:12:26,019 So this is how you have to proceed on this Excel file and this calendar, 130 00:12:26,019 --> 00:12:32,139 so that I see you know how to use Excel and how you have used it for the calendar 131 00:12:32,139 --> 00:12:37,559 to see how many days each of the eras and eons will be. 132 00:12:37,840 --> 00:12:39,679 Okay, so that is enough. Goodbye.