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72 CB 1.3 GENETIC VARIATION
USING KNOWLEDGE OF GENETICS
DNA Profiling and Species Identification
Traditionally, scientists identified species based on how they looked, how they behaved and
where they lived. Furthermore, they noted that a member of a species will readily interbred with
other members of that species and produce fertile offspring (i.e. offspring that are capable of
producing more offspring). For example, a cat and a dog look and behave differently. Secondly,
they cannot produce offspring. Therefore cats and dogs are different species.
Today, advances in genetic technology mean that scientists can now compare DNA profiles of
organisms to determine if it is genetically different from others, and therefore a different species.
DNA Reveals Giraffes Are 4 Species - Not 1
Finding could alter conservation strategies for these long-necked animals
Though scientists have noted for years
that giraffes have slightly different
patterns of spots and horn shapes, they
were considered one species since
individuals from different populations
readily interbred in captivity.
After years of believing all giraffes
belong to one species, scientists have
found there are actually four different
species of giraffes. According to DNA
analysis, giraffes have been spilt into
the Southern Giraffe, Northern Giraffe,
Masai Giraffe, and Reticulated Giraffe.
Dr. Axel Janke, along with Julian
Fennessy from the Giraffe Conservation
Foundation in Namibia and their
colleagues, tested the DNA of nearly 200
giraffes from across Africa. They found
that differences in their DNA profiles
were high enough to classify the groups
as distinct species.
The new finding has important
implications for giraffe conservation, Dr.
Janke said. Over the past 30 years giraffe
numbers have dropped to about 90,000
individuals from about 150,000. Right
now there are only about 5,900 northern
giraffes and 15, 950 reticulated giraffes.
“These 90,000, split up over four species,
makes it immediately clear that the
giraffes are threatened,” Dr. Janke said.
“You see immediately there is urgent need
for protection.”
Masai giraffe
Giraffa tippelskirchi
Population: 45,400
Reticulated giraffe
Giraffa reticulata
Population: 15,950
Southern giraffe
Giraffa giraffa
Population: 49,850
Northern giraffe
Giraffa camelopardalis
Population: 5,900
1. Outline why scientists originally thought there was only one species of giraffe. 




2. Discuss how scientists were able to identify four separate species. 







3. Describe the implications of this research for giraffe conservation. 






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