Killer whale menopause evolved from mother-daughter conflict
Biology / Evolution

Killer whale menopause evolved from mother-daughter conflict

From Cosmos Magazine, January 13, 2017 (Image: Shawn McCready via Flickr) Menopause is an evolutionary anomaly. Only in three species – humans, orcas and short-finned pilot whales – does female reproduction grind to a halt part-way through life. For orcas (Orcinus orca), a new study published in Current Biology shows that menopause isn’t just a … Continue reading

Evolution

On multicellularity and slime molds

Human beings are great big conglomerates of millions upon millions of cells. In this respect, we are very similar to other animals, as well as land plants, algae and filamentous fungi — we are multicellular. Multicellularity is thought to have evolved independently several times throughout history. Traditional thinking was that the ancestors of land plants evolved … Continue reading

Evolution

Reproductive quirks (part 2): Why did menstruation evolve?

As I’ve noted previously, humans are strange beasts and our reproductive biology illustrates this well. Menstruation and menopause are both rare in the animal kingdom. Of all mammals, only us, our primate relatives and elephant shrews menstruate. Menopause is even harder to come by — killer whales are our only sisters in hot-flushes, apparently. This … Continue reading