A bat with few friends and a short life
Group size, survival and surprisingly short lifespan in socially foraging bats
尽管许多蝙蝠物种在大型羊群中栖息，但更稳定的社会群体也相对较少。南美帕拉斯（Pallas）的Mastiff蝙蝠生活在此类群体中，个人窃听了其他团体成员的回声定位，以帮助找到他们的昆虫猎物。
A team of researchers at Max Planck Institute of Ornithology, led by Yann Gager, conducted the first detailed investigation of social structure in these bats. They predicted that the bats would live in small groups, because of the difficulty of co-ordinated flight and likelihood of acoustic interference if the bats foraged in big groups. Or, to put it another way, too many bats would just get in each other’s way. This prediction was proven correct: Pallas’s mastiff bats live in small (but stable) groups of 3-13 individuals.
A more surprising finding was the short lifespan of these bats; just 1.8 years on average, over three times less than the average bat lifespan. The researchers suggest this result’s from the Pallas’s mastiff bats highly specialised diet, feeding on ephemeral insect swarms that only appear at dawn and dusk. A life lived on this “energetic edge” seems to be a short one.
Nematodes in the tropics
Nematode worms are a diverse group of more than 20,000 species (including the classic model speciesC.elegans)和非常丰富;一个估计的措施ted that 4 out of every 5 multicellular organisms on the planet are nematodes. Yet for all their abundance, we know astonishingly little about their lives in the wild. For example, there are some indications that nematodes are less species-rich in the tropics than in temperate zones, which would be in stark contrast to most other animal groups. However, this might just reflect our ignorance of nematode diversity and abundance in these regions.
Gerhard Zotz and Walter Traunspurger looked to fill these gaps by investigating nematode diversity in the freshwater habitats created by water trapped in the crowns of tank bromeliad plants in Panama. They found 89 species of nematodes, of varying feeding types, with individual plants containing up to 25 different species. Notably, after rotifers, nematodes were the most abundant animals in these micro-habitats. This suggests that nematodes are actually likely to exist in considerable diversity and abundance in the wider tropical ecosystem; we just need to look for them.
A gut feeling that size matters
Vertebrate bacterial gut diversity: size also matters
越来越多的研究表明，肠道中细菌的多样性对其动物宿主具有重要意义。尽管许多因素似乎会影响个人肠道内的细菌多样性，但以前没有研究过相对简单的因素：大小。众所周知，在其他栖息地中，更大的尺寸通常意味着更大的多样性，那么在动物肠道的栖息地中也是如此吗？
A team of French researchers at the INRS, led by Jean-Jacques Godon, compared bacterial diversity in the guts of 71 species of birds, reptiles, and mammals (including humans). They found a strong correlation between gut size and diversity, with larger animals generally having a wider range of bacteria present in their guts. Gut volume should therefore be considered along with other parameters when explaining why diversity varies among species.
Boundaries are important for urban rabbits
Importance of latrine communication in European rabbits shifts along a rural-to-urban gradient
For many mammals, communication networks are based around deposition of excreta in latrines. These latrines can be formed at the edge of territorial boundaries, for between-group communication, or around key areas of the home range, for within-group communication.
Which type of latrine communication is more important for European rabbits seems to depend on whether they live in rural or urban areas. Urban rabbits locate latrines in higher proportions at the edge of their territories, in contrast to rural rabbits who locate more latrines around their burrows.
当时，农村兔子似乎优先考虑其社会群体中的沟通。对于城市兔子，群体规模较小，人口密度较高，组间交流似乎更为重要。当您有这么多邻居挤在您周围时，确保每个人都知道他们的界限变得至关重要。这项研究提供了对人造栖息地可以对动物行为产生的改变的新见解。
Citizen science: through the looking glass
公民科学 - 与专业科学家合作的公众收集数据 - 在生态学领域具有特别的潜力。生态研究通常需要在多年的时间内从遥远的位置收集数据。对于一个甚至多个研究小组来说，很难收集。利用更广泛的公众可以允许收集更广泛的数据集，从而使公众参与生态研究的额外好处。
当然，公民科学遇到了许多挑战，这些挑战在评估英国露天实验室国家公民科学网络的成功的文章中进行了讨论，现在已经接近了10个thanniversary. What makes lay-people keen to become involved with research, the quality of the data they gather, and the results arising from these studies were among the topics discussed.
Collection organiser Poppy Fraser Lakeman discussed these issues in more detailon our blog.
A cockroach in disguise
Attaphilacockroaches make a living by sneaking into the nests of leaf-cutter ants. These ants farm a fungus that provides an ideal food source for the invading cockroaches. Research led by Volker Nehring and Patrizia d’Ettorre at the University of Copenhagen investigated how the cockroaches steal food from a heavily guarded ant colony without being detected.
行为实验表明，蟑螂能够用蚂蚁用来识别其巢穴的菌落特异性表皮化学剖面掩饰自己。蟑螂没有受到他们所居住的同一殖民地的蚂蚁的攻击，而是受到其他殖民地的蚂蚁的攻击。化学分析证实，蟑螂复制其宿主菌落特异性表皮化学剖面。
研究这些蟑螂也使我们李尔王n more about how the ants themselves communicate. Cockroach species with lower concentrations of cuticular chemicals were less likely to be attacked by ants from other colonies. This supports the asymmetric model of ant nest-mate recognition; rather than ‘knowing’ their colonies specific profile, ants just respond to any unfamiliar cues; hence cockroaches with fewer chemical cues are less likely to find their disguise being uncovered.
狩猎作为管理工具？
当大型掠食者在人类定居点附近漫游时，冲突可能不可避免。管理这些压力的一种常见方法是允许人类猎人去除人类定居点附近的掠食者。假设是减少了人类预言的冲突：这项研究挑战的假设。
研究人员分析了加拿大猎人引起的美洲狮死亡率的30年数据集，研究人员发现了一个清晰的美洲狮奖杯狩猎模式increasinghuman-cougar conflict. They note that trophy hunters focus on the largest males, yet it is usually smaller, younger males that are more likely to come into conflict with humans. Removing large resident males may also disrupt cougar social structures, dispersing cougars over larger areas and making conflict with humans more likely.
这项工作增加了越来越多的证据表明，狩猎提供了一种贫穷（通常适得其反）来管理与大型掠食者冲突的方法。
Authors Kristine Teichman, Bogdan Cristescu and Chris Darimont discussed their research in more detailon our blog.
恐龙分布
A long-standing – and somewhat perplexing – problem in dinosaur ecology is the apparent high levels of diversity of large-bodied dinosaurs in North America during the Cretaceous period. Unlike modern-day large-bodied vertebrates where a few species, such as wolves and caribou, roam across very large areas, their dinosaur equivalents of 70 million years ago lived in much narrower ranges.
多伦多大学的托马斯·库伦（Thomas Cullen）和戴维·埃文斯（David Evans）通过研究加拿大艾伯塔省晚白垩纪的化石微壁物质来评估这些模式的原因。微观物是小骨头和牙齿的集中组合，被认为在沉积时可以很好地表示社区组成。
The prevailing theory to explain high dinosaur diversity is that these species were particularly sensitive to environmental changes, preventing them from roaming across large areas. The researchers tested this by comparing dinosaur diversity at two environmentally distinct microsites from the same time period. Contrary to this theory, there was no difference in relative abundance of different dinosaur taxa in these differing environments. A different explanation would appear to be required to explain this perplexing historical pattern.
Then and now: tracking the decline of an iconic tree
The Clanwilliam cedar is one of South Africa’s most iconic trees. It is also one of its most endangered. Tracking declines in long-lived species like the Clanwilliam cedar is difficult due to a lack of historical data, but this study demonstrated a novel way of doing so using repeat photography.
Researchers at the University of Cape Town, led by Joseph White, tracked down 87 historical photos of Clanwilliam cedars (stretching back 80 years) and meticulously recreated these photos, creating a visual record of population changes. The photos suggest tree numbers declined significantly over this period, but also suggest which habitats are best suited to their survival, which should help focus future conservation efforts.
We covered this paper in more detail in thisvideo blog.
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