Researchers attached miniature cameras to cuttlefish to study their hunting strategies and camouflage techniques from the prey's perspective. The footage revealed how cuttlefish use dynamic camouflage, rapidly changing skin patterns and textures to blend with the seafloor, making them nearly invisible to unsuspecting crabs. This camouflage allows cuttlefish to approach their prey undetected until they are close enough to strike with their tentacles. The study provides a unique viewpoint on predator-prey interactions and sheds light on the sophistication of cuttlefish camouflage.
Genetic analysis of killer whale scat collected around the Bremer Bay region of Australia confirms predation on white sharks. Researchers identified white shark DNA in multiple samples, including muscle and skin tissue. This provides direct dietary evidence supporting anecdotal observations of killer whale predation on white sharks in the area, including targeted attacks on the sharks' livers, a nutrient-rich organ. The study highlights the ecological role of killer whales as apex predators and their potential impact on white shark populations.
HN commenters discuss the methodology and implications of the study. Some question the small sample size (4 sharks with orca DNA) and suggest alternative explanations for the orca DNA presence, such as scavenging or secondary transfer. Others highlight the observed behavioral shift in white sharks avoiding areas where orcas are present, suggesting learned predator avoidance despite limited direct predation evidence. The discussion also touches on the ecological impact of apex predator interactions and the cascading effects on the ecosystem. Some express fascination with the topic and share anecdotal evidence or similar observations in other regions.
While squirrels are typically known for their herbivorous diet of nuts and seeds, recent observations and studies have confirmed that they also consume meat. Documented instances include squirrels preying on small animals like birds, snakes, and insects, sometimes even engaging in cannibalism. This carnivorous behavior, though surprising to some, is not entirely new and is likely driven by nutritional needs, especially protein scarcity during certain times of the year. These findings highlight the adaptable nature of squirrels and their broader role within the ecosystem.
Several Hacker News commenters point out that squirrels eating meat isn't novel or surprising. Many share personal anecdotes of observing squirrels consuming meat, including baby birds, roadkill, and even leftover chicken wings. Some highlight that squirrels are rodents, and rodents are opportunistic omnivores, so this behavior is expected. A few commenters criticize Gizmodo's reporting, suggesting the headline is sensationalized and misleading. Others discuss the adaptability of squirrels and their ability to thrive in various environments, with their diet reflecting available resources. Finally, some users humorously compare squirrels' opportunistic eating habits to their own scavenging for leftovers.
Summary of Comments ( 5 )
https://news.ycombinator.com/item?id=43254995
HN commenters discuss the amazing camouflage abilities of cuttlefish, with several expressing awe at their dynamic skin control and hunting strategies. Some debate the cuttlefish's intelligence and awareness, questioning whether the camouflage is a conscious act or a reflexive response. Others focus on the crab's perspective, speculating about its experience and whether it notices the changing patterns before being attacked. A few comments delve into the mechanics of the camouflage, discussing chromatophores and the speed of the skin changes. One user highlights the co-evolutionary arms race between predator and prey, noting the crab's evolved defenses like shells and quick reflexes, while another mentions the ethics of keeping cephalopods in captivity for research.
The Hacker News post titled "What a Crab Sees Before It Gets Eaten by a Cuttlefish" (linking to a New York Times article about cuttlefish camouflage and hunting) has generated several comments, offering various perspectives and additional information.
Several commenters focus on the remarkable camouflage abilities of cuttlefish, expressing awe and fascination with their dynamic skin patterns. One commenter points out the speed at which these cephalopods can change their appearance, highlighting the complexity of the neural processes involved. Another marvels at the effectiveness of their disguise, even against keen-eyed predators like sharks and dolphins.
The hunting techniques of cuttlefish are also a topic of discussion. One commenter describes the "passing cloud" display, where the cuttlefish creates moving patterns on its skin to mesmerize prey. Another mentions the hypnotic effect this has on crabs, making them easier to capture.
Some comments delve into the scientific aspects of the research. One user questions the methodology of the study mentioned in the NYT article, specifically asking how researchers determine what a crab "sees." Another clarifies this, explaining the use of cameras that mimic the crab's visual system, allowing scientists to understand the cuttlefish's camouflage from the crab's perspective.
The intelligence of cuttlefish is a recurring theme. Commenters discuss their complex nervous systems and advanced cognitive abilities. One user mentions the remarkable problem-solving skills observed in cuttlefish, including their ability to open jars and navigate mazes. Another draws a parallel to octopuses, highlighting the impressive intelligence found in cephalopods.
A few comments also touch upon the ethical implications of studying and potentially exploiting these intelligent creatures. One commenter raises concerns about the potential for using cuttlefish camouflage technology for military applications.
Finally, some commenters share personal anecdotes of encountering cuttlefish while diving or snorkeling, describing their beauty and otherworldly appearance.
Overall, the comments on the Hacker News post reflect a mixture of awe, scientific curiosity, and ethical considerations regarding cuttlefish and their remarkable abilities. They provide valuable context and further insights into the topic beyond the information presented in the linked NYT article.