Kind: captions
Language: en
let's talk tree
Basics an evolutionary philogenetic tree
is a depiction of how different species
are related to each other we'll start
with just one branch which represents a
single species like cushion sea stars or
human beings the top of that Branch
contains all the individual organisms of
that species so all people or all
cushion sea stars if we travel along a
branch back in time you come to common
ancestors of species when two branches
come together now let's roll time
forward Instead This split Point
represents the evolutionary moment when
a common ancestor species diverged into
two distinct species a process called
speciation as time goes on you get more
splitting more species and more
biodiversity until you get a tree that
looks something like this it's a
hierarchical
arrangement of how those organisms
originated and who they are more closely
related to a tree isn't a literal
timeline but it does show the passing of
time more ancient branches occur deeper
in the tree and more recent splits occur
closer to the tips for each puzzle in
this lab you'll be organizing a
collection of species into a tree start
by using the magnifying glass to learn
about the organisms explore the species
screens and the comparison screen to
track down the characteristics or traits
that different groups of species have in
common now not all traits are useful for
analyzing evolutionary relationships but
not to worry we've made sure to give you
mostly informative ones after you've
gathered the information you need build
your tree by dragging species icons and
then traits into the center of the
screen in general the more closely
related the species the more traits they
share deeper Branch points connect
species that are more distantly related
and have fewer traits in common when you
position a trait that location on the
tree corresponds to the common ancestor
where that trait first arose earn up to
two leaves in every puzzle one for
completing the tree and one for getting
the quiz question right the more leaves
you get the more complex you can make
your fractal tree which tracks your
progress through the lab after you
finish each puzzle you'll unlock the
next one or open up a whole new Mission
and you'll discover something about the
Living World pulsing all around you