We're still learning

Sometimes it seems like we think we know all there is to know about other species. People talk about man's supposed dominiom over nature and our superior intelligence. Yet there's still so much we don't know about the natural world - she keeps far more secrets than she has so far imparted to us. It's hard to prove how much we don't know, so the best way to be reminded of how much we don't know is to keep an eye on new discoveries.

I always feel both humbled and amazed when I read New Scientist magazine. Every week there are reports of new discoveries about other species - sometimes niche, sometimes seemingly unimportant but with wide-ranging implications, and sometimes so fundamental they stop you in your tracks.

This week, here are the reminders from the New Scientist that we're still learning:

First observed carnivore pollinators

Sandra Lai and colleagues at the University of Oxford observed wild Ethiopian wolves feeding on red hot poker flowers. They lick as many as 30 blooms per trip, furry faces covered in pollen which is likely transferred between flowers. This is, so far as the research team is aware, the first observation of a large carnivorous predator nectar-feeding - and it might be more widespread than is currently recognised (which is, really, not at all).¹

Female chimpanzees create cumulative culture

Wild chimpanzees are becoming more technologically advanced over time as females, who move between groups, bring knowledge of things like how to build tools. The new knowledge is combined with existing knowledge in the group, to create new techniques - this coming together of ideas to create better ones is called "cumulative culture". We knew that chimpanzees pass skills to new generations, but this is the first time we've identified a link showing cultural skill development between groups. Andrew Whiten at the University of St Andrews and his team analysed data on tool usage and genetics and found that chimpanzees with the most advanced tool sets were three to five times more likely to share the same DNA than those who used simple or no tools - even if they live thousands of kilometres apart.²

We finally figured out how birds fly without a vertical fin

The pointy bit with the airline logo on that sticks up at the back of a plane isn't there for aesthetics - in fact, it's a huge drag (literally) and adds a lot of weight - both of which decrease fuel efficiency. But it's necessary because we don't really know how to fly without tail fins or vertical stabilisers. We see birds do it, but until now we haven't been able to replicate it. David Lentink and his colleagues at the University of Groningen created PigeonBot, a machine with 52 real pigeon feathers and a computer programmed with reflexive tail movements observed in birds. The PigeonBot can take off, fly, and land - all without a tail fin (just a tail...). The movements of the tail are far too complex for humans to manually control (other species have many skills we don't have) but it seems we might be able to programme computers to control tails to fly without vertical stabilisers by mimicking birds.³

Wild cavefish don't need sleep

Alex Keene and colleagues at Texas A&M University have been studying cavefish longer than one cares to dwell on. They observed over ten years ago that captive cave-dwelling Mexican tetra get hardly any sleep. Now, they've shown that wild cavefish don't need much sleep either. Most Mexican tetra are surface-dwellers in rivers; they have normal vision and are colourful - according to the study, they sleep for 3-6 hours per day. Cave-dwellers of the same species have poor eyesight or no eyes and little colour - they barely sleep at all. Incredibly, this ability to go without sleep has evolved independently at least three times, suggesting it fulfils an important need for the cave-dwellers.⁴

Cockles grow windows

Heart cockles are bivalve molluscs - sea creatures with two shells. They have a symbiotic relationship with algae living inside them. The algae need light to photosynthesise, but heart cockles can't open their shells very wide, so we were puzzled about how the algae were getting enough light. Dakota McCoy and colleagues at the University of Chicago have discovered that heart cockles have transparent calcium carbonate crystal structures in their shells that function like fibre-optic bundles. They're like windows, letting in light. The windows are even filtered; they're made from aragonite, which allows twice as much photosynthetically useful light through as harmful ultraviolet light. This sunblock technique could be used to protect corals, who also host photosynethic algae but are more delicate than heart cockles.⁵

Coral on the Great Barrier Reef

So there you go - five incredible discoveries about other species, and there's a new magazine every week. New Scientist also covers health, technology, materials science, astrology, and much more. This post isn't sponsored, I just love it.

I read the New Scientist in print, but here are the online articles:

¹ Ethiopian wolves

² Chimpanzee cumulative culture

³ PigeonBot

⁴ Cavefish

⁵ Heart cockles