Return to Video

How do scientists explore the past? | California Academy of Sciences

  • 0:02 - 0:05
    ♪ (music) ♪
  • 0:08 - 0:10
    Scientists ask a lot of questions about the world,
  • 0:10 - 0:12
    like "Why is the sky blue?"
  • 0:12 - 0:14
    "Why do the leaves change color in the fall?"
  • 0:15 - 0:17
    Why do some species persist, and others do not?
  • 0:18 - 0:21
    We're really naturally curious about what's happening in the world,
  • 0:21 - 0:23
    and so we do research to try and answer these questions.
  • 0:25 - 0:28
    What started out as a very big, ambitious project
  • 0:29 - 0:33
    to, basically, build the evolutionary tree,
  • 0:33 - 0:37
    the timeline, and the history for vascular land plants.
  • 0:38 - 0:42
    Plants are effectively the foundation for all terrestrial life.
  • 0:42 - 0:44
    By inferring a timescale for evolution,
  • 0:44 - 0:48
    we can better understand how plants managed to colonize Earth.
  • 0:49 - 0:50
    It's only been very recently
  • 0:50 - 0:52
    that such a project has even been possible.
  • 0:53 - 0:56
    We're at a really exciting and interesting point
  • 0:56 - 0:59
    in scientific discovery
  • 0:59 - 1:02
    where we've accumulated, and collected, and studied
  • 1:02 - 1:05
    this massive amount of data about the biology of living plants,
  • 1:05 - 1:09
    about the geological record, about the fossil record.
  • 1:10 - 1:12
    And then the molecular revolution happened,
  • 1:12 - 1:14
    and we started collecting DNA evidence.
  • 1:15 - 1:19
    And so one of our new challenges in science
  • 1:19 - 1:22
    is how do we incorporate this vast amount of information
  • 1:22 - 1:24
    that we've been collecting together?
  • 1:25 - 1:27
    These methods are fairly new,
  • 1:28 - 1:31
    they've only been developing within the last five or ten years.
  • 1:31 - 1:35
    So this is really an opportunity to field-test these methods,
  • 1:35 - 1:37
    to see how they would behave on real data.
  • 1:37 - 1:40
    We figured we needed just kind of a short little study group
  • 1:40 - 1:42
    to test our methods.
  • 1:42 - 1:46
    And some new phylogenies, evolutionary trees, and data
  • 1:46 - 1:50
    have been published for this group of ferns, the Marattiales.
  • 1:50 - 1:53
    So we took this data set, and we started working with it,
  • 1:53 - 1:55
    coding up these fancy analyses to do it,
  • 1:55 - 1:58
    and it turned out to be a very involved
  • 1:58 - 2:02
    and much bigger task and project than we had anticipated.
  • 2:03 - 2:05
    The fundamental surprise is that we could do it.
  • 2:05 - 2:07
    We definitely went through dark days of thinking
  • 2:07 - 2:09
    that this was not going to be possible.
  • 2:09 - 2:13
    This project is from the beginning and until now hugely ambitious.
  • 2:15 - 2:17
    One set of results, which is arguably the set
  • 2:17 - 2:20
    that the broader public will be most excited about
  • 2:20 - 2:22
    is the inferences that we were able to make
  • 2:22 - 2:23
    about how evolution happened,
  • 2:23 - 2:24
    when evolution happened,
  • 2:24 - 2:28
    how it is that plants were able to colonize land,
  • 2:29 - 2:32
    how plants were able to diversify, form forests,
  • 2:32 - 2:34
    basically, form the foundation for terrestrial life.
  • 2:35 - 2:37
    There's another set of questions
  • 2:37 - 2:38
    I think are also extremely interesting,
  • 2:38 - 2:41
    although, perhaps, to a smaller community of people,
  • 2:41 - 2:45
    which is how does one investigate questions like this?
  • 2:45 - 2:48
    So in some ways, that result is even more exciting
  • 2:48 - 2:50
    because it is building a tool kit,
  • 2:50 - 2:54
    building capacity for people to better understand the natural world.
  • 2:55 - 2:59
    Understanding the history of life on Earth places us as humans
  • 2:59 - 3:04
    within a broader context of what it means to live on planet Earth.
  • 3:05 - 3:08
    To me, there's no more important piece of information
  • 3:08 - 3:11
    than to understand the history of evolution and where we fit into it.
  • 3:12 - 3:16
    This helps us explain and understand how we influence the Earth,
  • 3:16 - 3:17
    how we influence the environment,
  • 3:17 - 3:19
    where we come from,
  • 3:19 - 3:22
    and what the effects could be if we destroy everything around us.
  • 3:23 - 3:24
    ♪ (music) ♪
Tytuł:
How do scientists explore the past? | California Academy of Sciences
Opis:

more » « less
Video Language:
English
Team:
California Academy of Sciences
Duration:
03:46

English subtitles

Revisions