Science Virtual Lab: Smithsonian Museum Of Natural History

Foosil Tracks: An unknown animal made these strange chervon-shaped tracks half a ____________ years ago on the rippled sandy floor of a shallow sea.
A) hundred
B) billion✔
C) thousand
D) million

Fossil tracks: The animal's track pattern has been named "Climatichmites."
No _____________ animal leaves similar track patterns.
A) modern✔
B) old
C) big
D) small

The Fine Art of Filter-Feeding. The filter-feeder is limited to "soupe du jour"- a brother of small ______________ and organic particles suspended in sea water.
A) boys
B) girls
C) organisms✔
D) animals

The Fine Art of Filter-Feeding. Competition for food has much to do with where brachiopods and crinoids live. By positioning themselves at different ______________ in the water and choosing food particles of a particular size the animals stake out niches themselves.
A) times
B) heights✔
C) temperatures
D) colors

Filter-feeders move into the spotlight. Brachiopods look like ________.
A) fish
B) kids
C) clams✔
D) animals

Filter-feeders move into the spotlight. Crinoids are __________ looking animals.
A) scary
B) cute
C) rock
D) flowery✔