There are two main groups of plant: those
that make seeds in order to reproduce, and
those that are seedless. Seedless plants
reproduce from spores.
PLANT EVOLUTION
Seedless plants are the oldest plants
on the planet, first appearing about
475 million years ago. Flowering
plants are the youngest, a mere
130 million years old.■ Liverworts
6,000–8,000 species
Liverworts are the earliest known
form of plant life. They are
generally small, leafy-looking
plants that grow in damp places,
and sometimes in water. The
umbrellalike structures are
reproductive bodies.■ Horsetails
20–30 species
We can tell from fossils that
today’s horsetails look very
similar to those living 300 million
years ago. Modern horsetails are
small plants but the ancient ones
grew up to 150 ft (45 m) high and
formed great forests.■ Mosses
12,000 species
Mosses do not have roots.
Instead, they take in water
through their leaves, which
means they can grow without
soil. They attach to bare ground,
trees, and rock using rootlike
hairs called rhizoids.■ Ferns
Around 12,000 species
Ferns are typically found in damp,
shaded places. They come in a
great variety of shapes and sizes,
from dainty miniatures to great
tree ferns with fronds (leaves) up
to 16 ft (5 m) long.SPORES
Spores are tiny cells that
can divide to form a
many-celled body. This
body contains sex cells
that can be fertilized
and grow into a
new plant.I’M A SURVIVOR
Ginkgo biloba is the sole surviving
species of a group of plant that once
grew all over the world, but today
grows wild only in China. Ginkgo fossils have been
found that are 160 million years old—and they show
that the plant has not changed in all that time.SEEDLESS PLANTS
LIVING WORLD
TIMELINE OF PLANT EVOLUTION
Liverworts and mosses—
the first
seedless
plantsConifers—the first
seeded plantsFlowering Plants475 MILLION YEARS AGO 390360 MYA 360290 MYA 135 MYAFerns(^7)
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7
Types of plant
Ferns store spores in capsules
on the underside of their leaves.
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