First off, we're not in the business of trying to figure out if an elephant never forgets anything. One can presume that even an elephant has left its cell phone at a restaurant once, or come in late with a rent check. But there's plenty of evidence that elephants have terrific memories in general, and they're not just good for counting cards or winning a part in the school play. Elephants' memories contribute to their remarkable intelligence in general.
Let's take an example. Between 1958 and 1961, Tanzania's Tarangire National Park experienced a terrible drought. In 1993, a second drought came to the area. Just like any other animal or person, elephants had to decide whether to stay in their area and hope the drought let up or take their chances migrating. Scientists found that elephant groups with mothers who had lived through the earlier drought left the park, while younger mothers stayed put [source: Foley]. Groups that left the park ended up having much higher survival rates.
Well, you think, what's so great about that? The smart elephants left the drought zone --seems commonsense. But keep in mind that the group of elephants that stayed behind had no matriarch old enough to have been a part of the first drought; there was a clear selective advantage in the memories of females who had experienced previous droughts [source: Goudarzi].
But long-term memory isn't the only bank that elephants use. They also demonstrate a strong working memory, which allows them to keep track of and even organize their social groups [source: Ritchie]. Elephants travel in large groups over wide ranges, and they keep track of family members within the group. Sounds easy enough -- until you realize there's 20 or 30 relatives to keep track of. But the elephants appear to use their sense of smell and memory to know the location of each member. When scientists surreptitiously deposited a urine sample of a trailing elephant in front of a leading elephant, the animals registered surprise. They seemed to remember where each elephant was in relation to them [source: Bates].
Elephants have also been shown to remember individual language differences. Researchers conducted a study where elephants were played recordings of men from the Masai -- who kill elephants to protect grazing land -- and the less-threatening Kamba tribe. Though both repeated the same phrase, a majority of elephants acted much more defensively to the Masai recording [source: AP]. So with evidence such as this, Elephants' memories have proven to be not just good, but incredibly useful.