DICHOTOMOUS
KEYS:
a set of paired statements that describe physical
characteristics of different organisms
DICHOTOMOUS KEY: NAME THAT POTATO CHIP!
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NOW IT’S YOUR TURN TO PRACTICE
USING A DICHOTOMOUS KEY!!
Practice classifying North Carolina leaves, fish, and
norns (aliens!) by using the dichotomous keys in your
packet.
fish
NC Leaf
Norn
CLADOGRAMS:
a diagram that shows evolutionary
relationships among organisms.
Based on PHYLOGENY:
the evolutionary history
of a species
Doesn’t focus only
physical characteristics,
looks at evolutionary
history instead
Cladograms can also be called phylogenetic trees.
DERIVED TRAITS
TRAITS = CHARACTERISTICS
Derived traits are characteristics or features that are
found in later organisms but not in earlier ones.
Derived traits are represented as small tick marks on a cladogram with the
name of the trait next them.
Organisms closer to one
another on the tree
share a more recent
ancestor than the ones
farther away from each
other.
PRACTICE
Jaws
Hagfish
Perch
Salamander
Lizard
Pigeon
Mouse
Chimp
Derived Characteristics
Lungs Claws/Nails Feathers Fur/M. Glands
PRACTICE
Jaws
Hagfish
Perch
Salamander
Lizard
Pigeon
Mouse
Chimp
x
Derived Characteristics
Lungs Claws/Nails Feathers Fur/M. Glands
PRACTICE
Jaws
Hagfish
Perch
Salamander
Lizard
Pigeon
Mouse
Chimp
x
x
Derived Characteristics
Lungs Claws/Nails Feathers Fur/M. Glands
x
PRACTICE
Jaws
Hagfish
Perch
Salamander
Lizard
Pigeon
Mouse
Chimp
Derived Characteristics
Lungs Claws/Nails Feathers Fur/M. Glands
x
x
x
x
x
x
PRACTICE
Jaws
Hagfish
Perch
Salamander
Lizard
Pigeon
Mouse
Chimp
Derived Characteristics
Lungs Claws/Nails Feathers Fur/M. Glands
x
x
x
x
x
x
x
x
x
x
PRACTICE
Jaws
Hagfish
Perch
Salamander
Lizard
Pigeon
Mouse
Chimp
Derived Characteristics
Lungs Claws/Nails Feathers Fur/M. Glands
x
x
x
x
x
x
x
x
x
x
x
x
x
x
PRACTICE
Jaws
Derived Characteristics
Lungs Claws/Nails Feathers Fur/M. Glands
Hagfish
Perch
Salamander
x
x
x
Lizard
Pigeon
Mouse
Chimp
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
You can also use this table to construct a cladogram!
To help you, you can make a venn diagram.
Hagfish perch salamander lizard pigeon mouse chimp
Jaws
Derived Characteristics
Lungs Claws/Nails Feathers Fur/M. Glands
Hagfish
Perch
Salamander
x
x
x
Lizard
Pigeon
Mouse
Chimp
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
Now you can use your venn diagram to fill out the
cladogram:
chimp
hagfish perch salamander lizard pigeon mouse
feathers
Fur; Mammary Glands
Claws or Nails
Lungs
Jaws
Hagfish perch salamander lizard pigeon mouse chimp
Jaws
Lungs
Claws/Nails
Feathers
Fur/M. Glands