How many chromosomes does a typical chimpanzee cell have?
Guess before you scroll — the answer is below
The answer
48 chromosomes
A chimpanzee cell has 48 chromosomes, arranged in 24 pairs — two more than the 46 in a human cell. Geneticists believe two separate ancestral chromosomes fused end-to-end into what is now human chromosome 2, which is why the count dropped by one pair somewhere along the human evolutionary line.
How to get close to this number
Anchor on humans and adjust by one pair. If you know the human chromosome count, this one is a single step away — and the direction is upward, which is the part people get wrong. Chromosome counts across related species differ by small numbers of pairs, so anchoring on a species you know is by far the most reliable route.
The intuition that misleads is equating chromosome count with complexity. It does not track: plenty of plants and amphibians carry far more chromosomes than humans do, and the number reflects how a genome happens to be packaged rather than how much information it holds. Great apes generally carry one pair more than humans, and that is a packaging fact, not a ranking.
The fusion story in the explanation is one of the cleanest pieces of evidence in evolutionary biology. Human chromosome 2 shows the signature of two ancestral chromosomes joined end to end — including telomere sequences stranded in the middle, where the ends used to be. The count difference is not a mystery to be explained away; it is a prediction that was confirmed when the sequence was read.
Where this number comes from
| Source | National Human Genome Research Institute |
|---|---|
| Figure refers to | 2023 |
| Last checked | |
| Unit | chromosomes |
Numbers move. If this one has drifted from its source, let us know.
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