Another great example are Avocados, Papayas, Zapotes, Honey-locusts and other American large-seeded fruit that have no known seed dispersal mechanism anymore. All the big mammals that like giant sloth (and again, the mammoth) that would eat the fruit and later poop the seed somewhere else are gone and it's kind of a surprise that so many of those survived the last 13,000 years (and nobody knows what we may have lost during that time).