Uniting past and present

This exercise is a part of Educator Guide: Mosses Tell Story of Retreating Ice / View Guide

1. Can you find another recent article about global warming and vanishing sea ice but from a different year? How do the records for different years compare?

Possible student response: The article “For three years in a row, Earth breaks heat record,” published 1/18/2017, recounts how 2016, 2015 and 2014 were the hottest years since record keeping began in 1880. As of the date of that article, the first 16 years of the 21st century were among the 17 hottest years on record, with the highest temperatures in the last three successive years. The article included a very informative graph of the changes in total global sea ice (millions of square kilometers) over a year, from 1978–2017. The total sea ice for 2016 and the beginning of 2017 was dramatically lower than in previous years.

2. Can you find other articles about “ancient” items that were dated with radioactive carbon (carbon-14)? Describe the items.

Possible student response: The article “Ancient Maya codex not fake, new analysis claims,” published 10/29/2016, describes 10 surviving pages of a hand-drawn, bark-paper book that was apparently produced by the Maya in the 13th century, making it the earliest known surviving manuscript from ancient America. The article “Ancient text gives Judas heroic glow,” published 4/29/2006, describes a 1,700-year-old Coptic Egyptian manuscript of the Gospel of Judas that was produced by a group of early Gnostic Christians. The article “Tailored Egyptian dress is the oldest ever found,” published 4/2/2016, describes a woven and tailored dress that was recovered from an Egyptian cemetery, which carbon dating revealed to be between 5,100 and 5,400 years old. (Students might find articles with many other examples.)

3. Can you find an article about bringing frozen Arctic moss back to life? How are the scientific techniques in that article similar to or different from those described in the article from the November 25, 2017 issue? 

Possible student response: The article “Mosses frozen in time come back to life,” published 5/27/2013, discusses how scientists recovered moss samples that, until recently, had been buried under ice on a different Canadian island, Ellesmere Island. As with this week’s article, the scientists used carbon-14 dating to determine the mosses’ age, and found that the mosses lived approximately 400 years ago. Unlike in this week’s article, however, the scientists tried to revive the old, “dead” mosses by giving them fresh nutrients, water and light. Four different moss types sprung to life.