Great excitement in some of the media over the observation that elephants in Mozambique seem to be losing their tusks (https://www.dailymail.co.uk/news/article-6584333/Elephants-EVOLVED-not-grow-tusks-Mozambique-national-park.html ). This just shows the power of strong selection pressures as male elephants lacking these large ivories will not be selected by poachers. Although the tusks can be useful in feeding and in intermale competition for mates, this is not much benefit if you are shot. Examples of 'fast' evolution are, however, not uncommon. In Australia, snakes have recently shown a big reduction in their gapes. This seems to be related to such skins not being able to ingest highly poisonous Cane toads (introduced to the country in a vain attempt to eradicate beetles from cane sugar crops) which would kill them.
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