what does a barn swallow egg look like
Barn swallow There are normally two broods, with the original nest being reused for the second brood and being repaired and reused in subsequent years. The female lays two to seven, but typically four or five, reddish-spotted white eggs.[2] The clutch size is influenced by latitude, with clutch sizes of northern populations being higher on average than southern populations.[55] The eggs are 20 mm × 14 mm (0.79 in × 0.55 in) in size, and weigh 1.9 g (0.067 oz), of which 5% is shell. In Europe, the female does almost all the incubation, but in North America the male may incubate up to 25% of the time. The incubation period is normally 14–19 days, with another 18–23 days before the altricial chicks fledge. The fledged young stay with, and are fed by, the parents for about a week after leaving the nest. Occasionally, first-year birds from the first brood will assist in feeding the second brood.[2] Compared to those from early broods, juvenile barn swallows from late broods have been found to migrate at a younger age, fuel less efficiently during migration and have lower return rates the following year.[56]
Polychaete Some polychaetes exhibit remarkable reproductive strategies. Some species in the genus Eunicie reproduce by epitoky. For much of the year, these worms look like any other burrow-dwelling polychaete, but as the breeding season approaches, the worm undergoes a remarkable transformation as new, specialized segments begin to grow from its rear end until the worm can be clearly divided into two halves. The front half, the atoke, is asexual. The new rear half, responsible for breeding, is known as the epitoke. Each of the epitoke segments is packed with eggs and sperm and features a single eyespot on its surface. The beginning of the last lunar quarter is the cue for these animals to breed, and the epitokes break free from the atokes and float to the surface. The eye spots sense when the epitoke reaches the surface and the segments from millions of worms burst, releasing their eggs and sperm into the water.[9]